Help a novice please?

[308lrnewb]

Hi, I tried posting a few times - for some reason I keep having troubles. keeping this short, for this try.

So, I walked in to a local rifle builder's shop.. blahblahblah. they use a bunch of their own house brand dpms parts on a dpms/sr25 receiver set. it is their own spec cut, so the handguard/receiver height is proprietary. Seems ok quality. I know a few people whom have the 5.56&variants builds.

How do I reduce recoil? I read about that XH slash buffer. worth the money? What type of negative or adverse effects/affects has it produced upon lower receivers? Mostly - does it damage the buffer detente bore?

I want to reduce time between my splits on repetitive firing. This is for a heavy metal rifle class. Going to be throwing 175gr sierra matchkings. Trying to zip them faster than 2550fps while using H4895 or varget powders.

The local builder wants to use their inhouse adjustable gas block. uses a 90* offset 'tuning set screw' that obscures/shrouds/limits the gas port. I guess with soft loctite and a general cleaning regimen it will be ok.

Looking at 18" barrel(1:10 twist) with rifle length gas system and a rifle length buffer tube.

That jp full mass high pressure special something or-nother $500 bolt carrier group set.. is it worth all that dough? They claim it is heavier than a standard dpms setup. How much heavier? If a carrier weight addition covers that extra mass, what is the real selling point?

What are some potential negative side-effects of increasing all this reciprocating mass and reducing gas volume? I want 110% reliability in adverse conditions with less time between follow ups. Recoil reduction is an added bonus. Extra weight is of no concern, due to where that additional mass will be in the rifle. I foresee it better balancing everything.

Anything I should know or be aware of? I would be grateful to many inputs of real experience. Please, no keyboard warrior jockey talk ok? Only input if you have a current functioning rifle, build them for a living or have sold yours in means for funding another build/paying for a second baby.

Thank you, the newb!

**edit** I somehow got this to go in site news and not general discussion.. *headshake* will an admin move this to the appropriate section please?

Edited June 25, 2016 by 308lrnewb

[shepp]

Welcome to to forum, from southern wi

 

i personally do not have the slash buffer but in my years here I have NEVER heard anything but rave reviews on them. 

[Robocop1051]

there are a few different ways to control "felt recoil" and the "muzzle rise" of an AR platform rifle... It isn't .308 specific, since the technology is all the same (just sized up/down depending on the caliber)

1. Add weight. A tungsten buffer... A fat bull barrel... an extra weight carrier system. They all add to reducing the felt effects
2. Control gas flow. You can reduce the gas flow through the gas block to allow the minimum required gas to cycle the firearm. This slows the cyclic rate, which reduces the impulse of the action. It is often recommended to reduce the weight of the working parts so that even more gas can be cut out of the system. This is where the JP LMOS started. I have seen titanium carriers and delrin buffers running a nearly weightless AR. It's all about controlling the gas so the rifle doesn't beat itself to death. The technology on this is semi-recent in popularity, only the last 3 or 4 years. There haven't been too many stories about LONG term effects.
3. Get a muzzle device. A decent gas brake will cut even more felt recoil, and can be purchased for under $75. Compensators are best for eliminating muzzle rise, but require a bit more machining. They can usually be found around the $100 mark.

 

It's all about find the happy medium. The 308AR will very quickly get into the 13-15 pound range. I never recommend trying to build a "jack of all trades" .308 rifle. It'll never be as good as you wanted it to be. The 308AR is a pretty mission specific firearm. If you want a hunter, build a hunter. You want a long range paper killer, build that. If you want a combat rifle, it'll be heavier than a hunter and lighter than a bench rifle... but not quite as efficient as either in their specific fields.

No one says you only have to have one!!!

[308lrnewb]

I am aiming more for the combat build than anything. Something that will use xm118 style loads. Idea was a VCOG, a2 buttstock and grip with a floated tube. seekins k20 grip and a rhodesian sling from andy's leather.

Just want it to be extremely reliable. Willing to settle for 1MOA from 100-300m and 1&1/2-2moa from 400-600m. Hoping a decent floated barrel with a dialed in hand load will hit sub 10" five round groups at 600m.

What is the weight range we are talking here? The bare bones rifle with 'stock' dpms components weighed in at 9.3lbs - no mags or back up sights. I was estimating 15lbs with a full 25round pmag, vcog, metal magpul backups and the aforementioned accessories. Yea, I know - heavy. I also am aware of how 'weight' reduces recoil. Hoping it will be reasonably decent for accuracy, handling and longevity. I am not looking for a hunting rifle by particular.. Just something that with 180gr soft point handloads I can knock a deer or elk down when less than 300 yards away(little less than 300m).

This is meant for as tight a group possible in run/gun scenarios. going to be using it for some biathalon stuff, multi-gun, etc etc. it will be lugged almost everywhere I go on foot. has to bang/boom in real world adverse conditions. rain, snow, sleet, cold, hot and dry. It will be used in rapid succession type firing. not worried about ten rings or anything else.

I was figuring even with the 'extra mass' in a heavy buffer, that the operating properties of this gas system and bolt mechanism would provide minimal muzzle flip/rise. These rifles as a whole when using impingement tend to not buck.

Thank you to everyone so far - any more inputs would be great!

The newb

[blue109]

One piece of advice I can give

The biggest gripe most people have with these big frame guns is lack of standardization. It makes it hard to troubleshoot and upgrade.  Adding more proprietary or house brand stuff can complicate the issue. Not a big deal if they are building a complete rifle and testing it for you, and you have no plans to swap parts around, but still something to think about.  

 

Muzzle device will make a huge difference in how the gun feels, but it's a game of tradeoffs. Best recoil reduction will be obnoxiously loud etc. 

 

These piggies get heavy quick

[shepp]

8 minutes ago, blue109 said:

One piece of advice I can give

The biggest gripe most people have with these big frame guns is lack of standardization. It makes it hard to troubleshoot and upgrade.  Adding more proprietary or house brand stuff can complicate the issue. Not a big deal if they are building a complete rifle and testing it for you, and you have no plans to swap parts around, but still something to think about.  

great advice right there!!

[308lrnewb]

blue109, I hear it! I spoke with the local group enough to know their receiver set is basically a house spec dpms. unique flat top height for some reason about gas tube support. basically, it takes their own dpms barrel nut hand guard. any tube for dpms sr25 will work, just not line up with the top rail. if using the non railed carbons, etc etc it works just fine.

I think the main purpose was, due to the 'look' it has. not like most of the generics.

I agree entirely about the issue of cross compatibility. Also, with the weight. it adds up pretty fast.

Any other help or advice about these things? I am really just trying to get explicit reviews and direct 'I did this, and it yielded that' type of responses right now.

Seems like the 10oz slash buffer with standard bolt carrier group and tweaking this gas block should do about everything i want?

What are some recommended brakes? I was leaning to that procomp by surefire. Cheap, looks reasonably well made and most 5.56 guys say the 'baby' variant works well. To hell with noise. It just means 'get off mah propertah!' ;-)

Thank you all again,

The Newb

[308lrnewb]

 dislike double posting - failed to edit in time..

see: http://www.blackdawnguns.com/?product=black-dawn-bdr-10-308-receiver-set#

I hate to throw out anything beyond this link. For certain reasons. They have an online review of a 243 build. When I was in the shop last week, it was hanging on the wall. Apparently, they built a few 308 rifles for shooting competition prizes and the such. According to a few of them, some group was doing a review on the 308 chambering but for some reason closed up and did not publish the review before ending their business? *shrug*

[blue109]

I love shopping local, so I understand. I have one 556 gun that's almost all AZ built parts. With that said....I'd suggest skipping that upper. Some where, some time, you are going to want a different handguard.  It's a fact. You are limiting yourself, and hurting your resale value should you choose to go a different direction.

I like to build guns with basic, but quality parts. Standard gas blocks, standard buffers, regular BCGs. If there is an issue, work it from that baseline. If not and the gun runs great...why throw money at fancy stuff? Not saying it's the best approach, just saying it's been working for me. 

 

If you do upgrade later, at least you can feel the difference between the fancy parts and the standard parts and decide if the upgrade is worthwhile. The take off stuff can be sold, or end up in the parts box to birth shiny new builds.

I think you said you wanted an A2 stock? The standard DPMS 308 rifle buffer is heavier than a heavy carbine buffer, so no real need to upgrade there.  

Consider a 16" barrel. Save a little weight, save a couple inches for maneuverability. Not much appreciable accuracy loss unless you are shooting really far.  

 

[308lrnewb]

I am likely to never change handguards though. The keymod seems to be easily adaptable for most things, be it directly keymod or a 1913 rail attachment. I also value the input. Was thinking the 18" would be the best compromise. 16" providing issues with reaching out. The 18" should retain enough velocity to make a 600m shot reasonable. Yea, I have been told the 16" will do that. The guys had a 18" Liberty barreled (broached Satern barrel) keymod railed rifle on their wall for display. As stated previously, weighed in between 9.2 and 9.3 pounds. scale kept changing. This was minus magazine and sighting means.

The handguard will also support the MOE attachments where the slots are. *shrug* Also, I was not intending to ever sell either. Simply.. the group is expanding, I know most of their sponsored shooters as well. Interest was expressed in my concept of a build. They are asking $2000 for the complete rifle in my color of choice equipped with the a2 butt, grip, procomp brake, barrel listed above and a two-stage cmc trigger. It seems pretty reasonable. I know the upper and lower are matched sets, each one made specifically mated. For a few bucks more, I can pick up some magpul flip ups and the seekins k20 angled grip then mount my sling(already on the bench). Gets me almost completely set for the rifle bays, minus those xm118 magpul magazines and rounds.

I too was thinking about skipping the heavy buffer and seeing how it all played out. They swear that the 'tune-able' gas block makes the rifle very comparable to most m4's.

Am just in this for a one rifle can-do go to setup. No, it will not be agile as a carbine. No, it will not stretch out like a bolt action. It is being geared for 50m-600m, with enough leg room to make a hit/miss gong shot out at ~800 yards for bonus points. I live in a very rural area, if it has not been guessed. Will be packing this thing across fields and through small forests when out-and-about. Excuse being, better conditioning for the biathalon and long days at multi-gun events. The barrel is fluted from the nut to gas block. Looks like a pretty decent bull contour, but after gas block it goes to a straight .750 inch diameter. Pound for pound, it weighs a bit less than my dad's dpms gas-piston(non impingement) carbine. That dpms has a standard contour 16" barrel and a 3-9 power second focal plane lens. It has a bit of kick even with a brake and is not exactly my cup of tea. Sure, it swings a little bit faster due to the shorter length barrel. I am not using this thing at less than forty yards. Less than that and my 1911 colt is out.

The other end of it was, I had considered that Rainer Arms ultra-match 308 ambi-everything receiver set. It is high profile dpms. *shrug* but, no opportunity of applying for sponsorship or implied warranties with this route. The mega arms maten and the rainer arms both look nice. However, it seems odd to have an adjusting set screw for tension if they are billet receivers. =\

Thanks! Appreciate all the time and input guys/gals!

[Fletch]

I'm not 100% sure but I have a build that is along the lines of what you're talking about/hoping for (although mine is set-up more for a DMR/CSASS type of role). I'm not going to get into your choice of receiver(s) as I think blue109 pretty much hit that perfectly. Regarding the gas/recoil "system" itself all you really need is an adjustable gas block and a good muzzle device IMO. I see no point in getting a heavier-than-normal bolt carrier (JP FMOS for example)...or heavier than normal anything for that matter...UNLESS you weren't going to use an adjustable gas block or were getting a really heavy barrel and wanted to balance the weight of the build a bit better.

I run a 16" Mega Arms barrel with a Syrac Gen 2 click-adjust gas block (highly recommended...easy as heck to change and no set-screw to play with), a VG6 Gamma 762 muzzle break (also works great), and I do have one of Slash's Heavy Buffers (which does make a difference in smoothness IMO...although that is not why I bought it). The BCG is a Rubber City Armory with one of their high pressure bolts. Rifle itself (empty) weights a tad over 8 pounds. I can consistently get 3/4 inch groups with Fed GMM 168's and have gotten a handful of 1/2 inch groups as well. I tried 175's also but this barrel seems to prefer the 168's (at least with the factory ammo...I do not reload). The rifle is 100% reliable and cycles very smoothly...recoil and muzzle rise are very tame. I will say that I don't really do a lot of rapid-fire with this build but on the few occasions that I did it ran perfectly.

I got the Slash Buffer (and spring) because when I first built the rifle I used the standard DPMS-style 308 carbine buffer...but the cycling force kept compressing the stopper on the DPMS buffer to the point that it would allow the bolt carrier to impact the area of the lower receiver where the buffer tube is screwed in causing a little denting/dinging (even with an adjustable block). The Slash Buffer is constructed more solidly and seems to fit the buffer tube better (less jiggly?), the stopper is thinner and appears more solid and seems much less prone to the compression that I was experiencing with the DPMS buffer. After I made the switch there seemed to be a noticeable difference in the smoothness and cycling.

 

 

Edited June 25, 2016 by Fletch

[survivalshop]

  I have a 20" HB , 18" med. & a 16" HB, all Criterion barrels on DPMS type Receivers ( the 16" & 20" have actual DPMS Receiver sets ), the 20" HB is a beast ,but will print one hole groups with my hand loads 168's & 175's . The 16" will do as good as the 18" & with those two I went to 155 gr. .Though the 168's do a bit better ,I don't have a range close that I can shoot past 200 yards & the 16" will shoot sub MOA at that difference, if I do my part , so its why I went to the 155 gr. . Just not much of a difference at that range between all three , I have no doubt about the 16" holding its own at 600 yards with good glass .

  My 18" has a Magpul MOE Rifle Stock & my 20" has an A2 , the Magpul is a much better rifle stock to me . 

 I don't believe in any of that fancy stuff ether , All my Barrels have Rifle length gas systems , std BCG 's & DPMS Buffer's & springs ( 18" has a Tubb's flat wire spring & works great , only sing I had around at the time tat was correct for a 308AR )  , non adj has blocks .The 16" Has a Magpul CTR Stock & the rifle has a little kick , but its a 308 & on the lighter side compared to the other two , all Have some kind of Brakes & they all do what is meant of them , I could care less about noise , I wear ear protection .

  Slash ( Heavy Buffers ) maks a good product & they work , I just do see the need except as you say you want a .22 recoil from a 308 , it will help .

 As has been said , around here we seem to hear more issues with proprietary components then Factory copy types . It is good you want to stay with the Matched or same Manufacturers Receiver set .

  Theres a lot to a consistent shooting rifle , the 16" BBL. is a better all around rifle , would not be my pick for a Bench gun for a 1K yards, but will hold its own with a good Barrel , Trigger , ammo & the most important , a good shooter .

  Photo of the 16' & 20" , though the Upper Receiver, Hand guard & Scope reside on the 18" now , as seen in next photo . I'll get a recent one on the 16" later .

18"

[308lrnewb]

sharp shooting! You mean the set screw with the detente? I looked at syrac's webpage. midway says discontinued. hmm.. 

Why is the general thought I will want to change my float tube? I handled a fully assembled rifle with the exact tube just last week - felt fine. a few BCM keymod rubber inserts are easily fitted, if any issues arise. I am just confused here. Please enlighten me =D!!

It may possibly be barrel harmonics or just a generally 'wrong' amount of charge weight/type for your rifle, with the 168's being better. sometimes, it is hard to tell as rifles get picky.

How far are you capable of hitting with that rifle? Know what your muzzle velocities are looking like with federal gold match?

What are the reviews on those rubber city bolt carrier groups? Their high pressure 308 bolt carrier seems a bit cheaper than the JP similar offering. Although, I am unsure why it is fluted.. *shrug* maybe that with an adjusted gas system will do the trick for powder puff recoil. AHAH!

It seems to me, you are using the M4 buffer tube extension. Does that mean you are using the 5.5 or 6.5oz buffer?

 

@  survival shop 

Them are some slick rifles as well. You do not see any need for the heavy buffer either? Well, alright. I am just trying to get something that works. I always liked those round tubes you show on the 18" rifle. They capable of any attachments, or is that just one of them fancy low weight ringer-dingers?

So, in a go to grab it and run rifle - the sixteen inch barrel is your pick huh? Any reason why?

 

I keep seeing all of these spacers to use carbine buffers and springs in a rifle length extension tube - why? Someone educate me. Also, are there any of those high density tungsten powder filled 308 buffers?

I was under the impression that the rifle length extension tube and rifle buffer/spring combination would 'smooth out' must recoil impulses, in comparison to the carbine lengths. such as, if both tubes were used with identical weight buffers, the carbine length buffer/tube would still 'kick' more. 

MORE HELP PLEASE!! by the truck load..

[survivalshop]

  The rifle length Stock will perceive less recoil for a number of reasons , one being a larger Buffer & spring & in the Magpul MOE , a good Rubber recoil pad .

 The Hang Guard on the 18" is an Early JP 's VTac ( pre 2009 ) , 308AR , with full length top Rail ( rail is an Exta $ 90 ) , other rails can be added at the normal positions .

 Why the 16" , just handy to carrie & swing around & slightly lighter , more compact with the Collapsible stock system. I have a Burris 6.5x22x50 on it , but was installed only to have a good comparison shoot out with the other two . I will go back to Iron sights only ,when done, I like Iron sights even with my old eye's.

  I would stick with std rifle stock components if using a rifle stock system. 

[308lrnewb]

Thank you for the inputs! I was thinking the same thing about rifle stock.

I only like the A2 buttpiece because I need a swivel on the bottom, not one of those new aged fangled up "QD CUPS" on the side for some slicked out nylon sling.

I am well aware the MOE buttpiece has a decently replacable rubber pad and some blind holes in the 6 o'clock position for rails. Unsure if I could put a sling mount in there with little to no issue. anyone have experience there?

I am thinking that my build preference is shifting somewhat. Maybe that rubber city bolt carrier group for $300, a standard buffer/spring combo and just spin the gas block a bunch to be hardly gassing at all. Probably going to stick with that 18" barrel though.

Was looking at the mech armor defense tacops charge handle and battle sights. a bit cheaper than other routes, plus seems to have good reviews. I do not mind the HK style front sight either.

I agree - irons are pretty handy and hard to beat.

The ONLY reason I ask about the standard style sling orientation is because I am slotted to use the Rhodesian Sling. I like being able to draw up for shots at range. Plus, that sling weighs a small truck tonnage of difference when compared to a bipod. Not to mention - doubles for when I am tired of holding this blaster...

[Fletch]

48 minutes ago, 308lrnewb said:

sharp shooting!  THANK YOU  You mean the set screw with the detente? YES, THE GEN 2 CLICK-ADJUSTABLE BLOCK...I HAVE THE SET-SCREW TYPE, NOT THE CLAMP. MY BARREL IS DIMPLED FOR A SET SCREW, OTHERWISE I WOULD HAVE GOTTEN THE CLAMP STYLE. I looked at syrac's webpage. midway says discontinued. hmm.. 

Why is the general thought I will want to change my float tube? I handled a fully assembled rifle with the exact tube just last week - felt fine. a few BCM keymod rubber inserts are easily fitted, if any issues arise. I am just confused here. Please enlighten me =D!!

It may possibly be barrel harmonics or just a generally 'wrong' amount of charge weight/type for your rifle, with the 168's being better. sometimes, it is hard to tell as rifles get picky.

How far are you capable of hitting with that rifle? 800 YARDS IS THE FURTHEST I HAVE SHOT IT. I'VE ONLY SHOT STEEL BEYOND 400 YARDS WITH THAT GUN (FULL AND 2/3 SCALE IPSC SILHOUETTE). I HAVE NO PROBLEM HITTING THEM CONSISTENTLY. THERE IS A 6" GONG @ 300 YARDS AND AN 8" GONG @ 400 YARDS AT THE RANGE I NORMALLY GO TO AND I CAN HIT THOSE CONSISTENTLY AS WELL. Know what your muzzle velocities are looking like with federal gold match? I AM GETTING 2465-ISH WITH THE 168'S...I HAVE NEVER CHRONO'D THE 175'S. I WAS EXPERIMENTING WITH HORNADY A-MAX 168'S FOR A WHILE, WAS GETTING AROUND 2500 BUT ALSO A LITTLE LESS ACCURACY THAN THE FEDERAL GMM.

What are the reviews on those rubber city bolt carrier groups? I'M NOT SURE WHAT THE REVIEWS HAVE BEEN, I CHOSE THAT ONE BASED ON MEGA ARMS SUGGESTION. THEY TOLD ME THEY USE RUBBER CITY BOLTS AND CARRIERS FOR ALL THEIR TESTING, ETC. (AT LEAST IN THEIR MATEN PRODUCTS...I HAVE NO CLUE ABOUT THEIR 5.56 STUFF) Their high pressure 308 bolt carrier seems a bit cheaper than the JP similar offering. IT IS...BUT I AM INCLINED TO THINK THE JP PRODUCTS ARE WORTH THE EXTRA MONEY FROM WHAT I HEAR/READ. Although, I am unsure why it is fluted..RCA HAS BOTH FLUTED AND NON-FLUTED FOR THE 308 CARRIERS FOR THOSE WITH/WITHOUT FORWARD ASSIST *shrug* maybe that with an adjusted gas system will do the trick for powder puff recoil. AHAH!

It seems to me, you are using the M4 buffer tube extension. YES, STANDARD AR-15 CARBINE BUFFER TUBE ( Does that mean you are using the 5.5 or 6.5oz buffer? I'M USING THE 5.5 OZ BUFFER. I GET NICE CONSISTENT EJECTION RIGHT AROUND 4:00-4:30. THE GAS BLOCK HAS 16 POSSIBLE SETTINGS...LET'S SAY 0 = CLOSED AND 16 = WIDE OPEN...MINE IS SET ON 7 AND IT RUNS GREAT.

I WILL SAY THAT THERE WAS CERTAINLY SOME TRIAL AND ERROR FOR ME WITH THAT BUILD...I STARTED WITH A DIFFERENT BARREL, A NON-ADJUSTABLE GAS BLOCK, A REGULAR FLASH HIDER, AND OF COURSE THE STANDARD DPMS 308 CARBINE BUFFER. I CHANGED BARRELS FOR A MORE ACCURATE ONE, THE SLASH BUFFER & ADJ. GAS BLOCK CAME ABOUT DUE TO THE ISSUE I MENTIONED PREVIOUSLY, AND THE BRAKE WAS A PRODUCT OF WANTING A MORE TAME RIFLE FOR BEING ABLE TO KEEP MY EYES ON TARGET (ESPECIALLY AT LONGER DISTANCES) FOR QUICKER FOLLOW-UP SHOTS. THE UPSIDE IS AFTER ALL THAT MESSING AROUND I FINALLY HAVE PRETTY MUCH EXACTLY WHAT I SET OUT TO BUILD. IT IS EASILY MY FAVORITE GUN AND IF I COULD ONLY KEEP ONE OF MY GUNS (GOD FORBID) THAT WOULD BE IT.

@  survival shop 

Them are some slick rifles as well. You do not see any need for the heavy buffer either? Well, alright. I am just trying to get something that works. I always liked those round tubes you show on the 18" rifle. They capable of any attachments, or is that just one of them fancy low weight ringer-dingers?

So, in a go to grab it and run rifle - the sixteen inch barrel is your pick huh? Any reason why?

 

I keep seeing all of these spacers to use carbine buffers and springs in a rifle length extension tube - why? Someone educate me. Also, are there any of those high density tungsten powder filled 308 buffers?

I was under the impression that the rifle length extension tube and rifle buffer/spring combination would 'smooth out' must recoil impulses, in comparison to the carbine lengths. such as, if both tubes were used with identical weight buffers, the carbine length buffer/tube would still 'kick' more.

MORE HELP PLEASE!! by the truck load..

 

 

[308lrnewb]

interesting to know, fletch. Thank you for helping cement some thoughts. That 5.5oz buffer in your carbine is about on par with the 5.4oz rifle buffer, so.. Do you really feel that the JP would be a better pick over the rubber city? I am almost inclined to think that JP comes with a premium cost. Materials seem the same. However, with their JP premium comes a bit of that well paid research department as well.. However, for $200 in difference.. These rifles can add up pretty quick in cost.

How did that RCA bolt headspace? The QPQ finish wearing decently? Anything else you can tell me?

[Fletch]

21 minutes ago, 308lrnewb said:

interesting to know, fletch. Thank you for helping cement some thoughts. That 5.5oz buffer in your carbine is about on par with the 5.4oz rifle buffer, so.. Do you really feel that the JP would be a better pick over the rubber city? I am almost inclined to think that JP comes with a premium cost. Materials seem the same. However, with their JP premium comes a bit of that well paid research department as well.. However, for $200 in difference.. These rifles can add up pretty quick in cost.

How did that RCA bolt headspace? The QPQ finish wearing decently? Anything else you can tell me?

If cost isn't an issue I would say absolutely go the JP route, but factoring in cost I would say go with the RCA. I have on occasion dealt with JP Rifles for a few things...each of those times I was completely impressed with their fantastic customer service and attention to every detail. They make great stuff and stand behind it 100%. But yes, a premium cost for sure. For myself, the primary advantage of the JP would have been the weight savings (I would have gotten their Low Mass BCG), but you mentioned looking at the Full Mass BCG, in which case the benefit of the JP might not be as big to you.

The RCA headspaced perfectly (using Clymer gauges)...just barely closed on the GO Gauge, but I've always heard that Mega is known for having tight chambers. The finish seems to be holding up quite well. Not much else to say about the RCA BCG...I haven't had one problem with it (knock on wood) which is most certainly a good thing!

[308lrnewb]

Thank you all again! Anyone know the weight of the JP low mass and full mass bolt carrier groups for comparison?

Glad to hear the input, Fletch. Any reputable barrel+extension should properly headspace with the RCA then, most likely..

Sounding like I am going to start working on a plan.

Coming out with:

-----------------

5R Liberty barrel by Satern. 18" 1-10 twist rifle gas system. is a medium/heavy contour with fluting beneath handguard. Possibly referred to as special purpose rifle contour? It showed a 'thick' medium contour beneath the handguard with i believe five flutes. 

RCA BCG - Looks pretty decent. Thank you for pointing this one out.

Local builder's receiver+float tube set and in-house gasblock.

CMC two stage trigger. feels like 3.5-4# *shrug* unsure on weight.

Surefire ProComp brake.

TacOps charge handle

Mech Armor flip up sights.

Seekins K20 foregrip.

A tricked out Rhodesian Sling from Andy's Leather. They are top quality, if you shoot like a scout.

------------

Going to be playing with H4895 powder and 168/175 sierra match kings while climbing ladders to dial in a blistering velocity that prints consistently. Want to say thank you to everyone so far! This is a great community. Unfortunately, I am not made of money and this is all my footwork before delving into a custom build. Local builder has a surplus of primary components (barrels included) so, I am hoping to have this thing going this fall or next summer. Saving up for the spring national pistol bays in Mesa AZ for 2017. If any of you are around that area when Rio Salado Shooter's Club hosts.. be there! That staff is amazing and puts on one heck of a show. Need to go visit my powder supplier and pick up a load large enough that rises FBI interest too. =O God bless Bush Jr. and his ability to remove our privacy.

If anyone has some insight, recommendations or tips from experience - please inform me!

Thank you all so very much,

The Newb

[Fletch]

You're welcome, glad to be of help.

JP lists their Low Mass carrier as weighing 10.82 oz and the Full Mass carrier at 15.31 oz (those weights are for the carrier only without a bolt)

Don't forget to give us a report once you have the gun built and running!

Best of luck to you!

 

[survivalshop]

  Are you building this rifle your self or having a builder do it ?

 As far as adj. the Gas Block on the Barrel , don't bother , your just asking for issues , if you want to adj. the Gas impulse , go with an adj.Gas Black ,like has been mentioned .

  You can look in the Reloading section & There is plenty of Chrono. results in there for different barrels , Powders & Bullet wt.'s .

Edited June 26, 2016 by survivalshop

[308lrnewb]

survivalshop - the gas blocks operate in similar function if I understand. Simply, the syrac uses a detente that prevents rotation where as the inhouse model is used with a loctite. Am I missing something here? I was probably going to opt for building it myself. Pick up the parts as funds allow. Save a few bucks in the process while retaining their 'rifle' for what ends I have behind that.

Seems I am a bit confused. Both of those blocks place obstructions in to the gas port. I was under the impression two very similar loads (one hunting, one for plinking) with a bit of compromise in 'recoil' I would be able to utilize both after the block was set.

More insight and input would be very appreciated!

Fletch - RCA shows their forward assist 308 bcg ringing in at 19.9 ounces. I would guess that both JP and RCA are almost toe for toe in the heavyweight full mass class.

[survivalshop]

17 hours ago, 308lrnewb said:

Thank you for the inputs! I was thinking the same thing about rifle stock.

I only like the A2 buttpiece because I need a swivel on the bottom, not one of those new aged fangled up "QD CUPS" on the side for some slicked out nylon sling.

I am well aware the MOE buttpiece has a decently replacable rubber pad and some blind holes in the 6 o'clock position for rails. Unsure if I could put a sling mount in there with little to no issue. anyone have experience there?

I am thinking that my build preference is shifting somewhat. Maybe that rubber city bolt carrier group for $300, a standard buffer/spring combo and just spin the gas block a bunch to be hardly gassing at all. Probably going to stick with that 18" barrel though.

Was looking at the mech armor defense tacops charge handle and battle sights. a bit cheaper than other routes, plus seems to have good reviews. I do not mind the HK style front sight either.

I agree - irons are pretty handy and hard to beat.

The ONLY reason I ask about the standard style sling orientation is because I am slotted to use the Rhodesian Sling. I like being able to draw up for shots at range. Plus, that sling weighs a small truck tonnage of difference when compared to a bipod. Not to mention - doubles for when I am tired of holding this blaster...

  Sounds like you want to move the gas Block on the Barrel to adj. for Gas signature , its why I said that. Do you mean spin the Gas adjuster on an Adj. Gas Block ?

  The issue with any Adj.Gas Block is , if you shoot different Ammo with different loadings , you ether have to make adjustments for each particular loading or set them for a wide range of ammo loadings , so the rifle functions with the wide verity of different loads you plan on using , by doing that , you can forget about your light recoil .

 

[308lrnewb]

Yes, I meant to turn the adjusting screw. What do you mean by moving the block in relation to barrel for gas signature adjustments? I am a bit confused. The position of the block in relation to the barrel can also affect things? This would make sense, with how much the ports are in line with each other..

I was also considering what you mention about a more broad range setting. If I am doing that, may as well go non-adjustable and run that heavy buffer by slash right?

Please, more information on adjusting gas signature!

Thank you so much!!

[survivalshop]

 The Gas Block is set  ( locked down , by pins, Screws or clamped ) on the barrel in relation to the Gas Port & is not moved , an adj. gas Block , through an adjustment screw ,plug ,port or what ever ) just adj. gas flow or Gas signature from the Barrels Gas Port or orifice to effect cycling of the rifles reciprocating Action components .( Bolt Carrier Group Buffer & Spring )  I think you knew that.