Jgun

My experience has been that the fit and finish of the DPMS .308 receivers/uppers I've used has not been as good as the Mega receiver set. If building for long rang accuracy a sloppy fit between the upper and lower can be annoying, although there are ways to "fix" the problem if you have it with the DPMS set. For myself, I would not be all that concerned about the 6061 vs the 7075 material, although I'd consider it a plus if the receiver I pick was of the better material. I'd be more concerned with how well the parts were machined. Since your interested in long range and are not planning to mount anything to it, a light weight free float tube will save you some money. Since you say that your not that conserned with the weight. I might suggest you take a look at the Magpul PRS stock. I recently picked one up and although I have not had a chance to try it out at the range yet, I really like the LOP and cheek riser adjustments, and I think it feels much more solid than the CTR type collapsing stocks. Good luck with your build.

Also saw this one for you guys that can own them. http://www.gunbroker.com/Auction/ViewItem.aspx?Item=299679819

For those of you that are still broken up about not getting a MA TEN monlithic upper, (and have money burning a hole in your pocket) I saw this on GB. Looks to be a well specd out gun. I didn't add up what the parts would run but it's probably not a bad deal. http://www.gunbroker.com/Auction/ViewItem.aspx?Item=299685481

I'm not that knowledgable when it comes to suppressor's and how much barrel overlap there is (I think it varies greatly depending on type/brand) but, if you have your barrl shortened to 20" and go with a handguard that just covers the rifle length gas block, you're going to have somewhere around 6" of barrel past the front of the rail. On my long range AR build, I went with a 20" barrel and a 15" rail and I've got over 4" from the front of the rail to the shoulder on the barrel that the brake locks against. Do they sell suppressors down there that overlap the barrel more than 6"? If not your going to need a pretty long handguard if you want it to meet or overlap the suppressor.

If you were able to tap it on with a screwdriver handle, I'm sure it will be fine, and you ought to be able to get it back off without too much trouble if you ever need to in order to change the gas tube.

I have not contacted Jim directly because I've already got a running Saiga and don't presently have the finances to get started with a new platform that may, or may not, be superior to what I'm already running. I saw some of the stuff posted on Enos, and the guys were lining up to buy his guns/mags, but I prefer to build myself, and the prospect of buying 8 to 10 (is that $140) mags in order to try out the new platform isn't something I'm likely to do without first trying someones gun and saying "Ive got to get me one of these".

First off, I want to apologize again for taking this thread in a different direction, I should have started one in the shotgun section, but I seem to do a lot of free association when I read these threads/posts, and sometimes questions just pop into my head. JeffreyC, good link there. it sounds like the heavy hitters in the comp shotgun game are all pretty much in agreement that the mag issue is whats holding the MKA 1919 back from taking off at the matches. Although I applaud what Jim's been doing with the guns and the mags, unless someone decides that there is enough money to be made, and tools up to manufacture hi cap mags in sufficient quantities that the price becomes more reasonable, I think that the Akdel gun isn't likely to catch on in a big way. And in this political climate I don't know if anyone wants to take the chance right now, to invest the time/money to bring a viable product to market only to have it declared ilegal. I also think that when/if they start being widely used in competition, that will be when the weaknesses, if any, of the design will become apparent.

If your measurements are in fact accurate, you have a .002" interference fit. Most people feel that it's not an ideal situation when you are creating a localized constriction on the barrel. Picture it this way, bullet travels down the barrel and reaches a point where there is a ring (gas block) squeezing it and then passes the constriction where the bore has no outside pressure on it. Now keep in mind, the barrel wall is thicker than the GB wall so the barrel stretches the GB bore more than the GB bore squeezes the barrel. But the problem is so easy to cure that there's no excuse not to do it. As 98 said tight is better than loose, I'd rather have parts that I can fit than parts that are a loose fit. I've heard people say that a loose fit isn't a problem because the carbon will fill and seal it over time but I've sent GB's back that were a loose fit. Also, in this case it's better to polish out the undersize GB than to remove material from the barrel. I usually remove material from the part that is out of spec, in this case the GB. You would be fine with a 1/2 thousandth under or oversize GB bore. This is an area where it may have no effect on the function of the rifle if you were to press the GB on as is, but most accuracy conscious builders wouldn't want the press fit, also the set screws on the bottom of some gas blocks, it is not a good thing to crank them down too tight, for the same reason, you create localized pressure on the barrel bore. Better to mark the spots, dimple the barrel slightly and snug them down just enough to hold the gb in place, and don't forget to use red loctite on those set screws.

In your opinion is the Rem 1100 operating system well executed by AKDEL in the 1919? Have you fired the gun? I have not seen them being used at any of the local matches, which may have more to do with the mags that are offered for them, than issues with the gun itself. I don't know of any company manufacturing 10/12 rd mags for the 1919 at the present time. As far as I know the high cap mags are all custom made right now.

I like their receiver and cf freefloat tube as well. Since there are already other platic mags on the market (Troy, Tango Down) I'm assuming your saying you'd like someone to offer a transluscent mag for the .308. I was wondering why Magpul hasn't offered a windowed .308 P mag as they have for the .223?

Yes thats it. I always call the gun by the company name because I can never remember the model name. I have seen that a number of the big Saiga builders, Tony Rumor of Tromix, Jim of Firebird Precision and Robert Right of R&R have all done work on modifying them for 3 gun. I saw that they had to mill the fixed polymer butt stock off and thread the back to take a receiver extension so that they can use a collapsing stock. From what I've seen so far I've taken a wait and see attitude. I'd still prefer it if someone would just make a 12 ga AR. As far as I know the 1919 just looks like an AR it doesn't use an AR operating system.

First off, I don't wish to be rude and hijack this thread but I don't know how I could have linked the question about the material used in the Akdel shotgun if I had posted it in the shotgun section. I presently have a Saiga (I posted pics of it in the shotgun section a while ago) and think it's a great gun, but If someone came up with a steel or aluminum AR type 12 ga I'd certainly be interested, I'd love to have a 12 ga that had the ergonomics of the AR. So far the nearest thing that I'm aware off is the AKDEL, but since it's polymer, I'm a little leary of it, hence my question. BTW, for the Saigas I like the Surefire mags, and I've got a red dot on mine because the box mag puts me in open division at the matches so I might as well have the optic, with my eyes it's a big help.

Wonder if those AKDEL 12ga shotguns, the ones that look like AR 15's, are made of the same type of polymer? If so I'm thinking that they might also have a short lifespan as compared to an aluminum or steel gun.

Is the B5 lighter or shorter (collapsed) than the ones that I am familiar with, CTR,MOE,ACS,etc? And since we're talking stocks, has anyone tried the Troy collapsing stock?

I have used an adjustable gas block on one rifle to date. The rifle was a 300BLK with a lightened bolt carrier that I set up for 3 gun. I did not use a heavy buffer in that one. for my application I found that the PRI adjustable worked as I had hoped and allowed me to set the gas impulse at the minimum that would cycle the action. This is a gun that I intend (had intended) to use with only one hand load. There are some members here that do not like the adjustable gas blocks but I found that the PRI suited my application well. Some say that if the gas system is suited to the gun (gas port in barrel correct size for the gas block location, and the caliber/load, there should be no need for adjusting the gas impulse with the block. In that context an adjustable gas block might also be considered a band aid for an over gassed gun. Most consider the .308 AR to be over gassed by design, when a suppressor is added the condition is aggrivated. I have used the heavy buffers and like them, others here feel that if the gun is set up properly they are not needed. They act by delaying the opening of the bolt slightly, which allows the pressure in the barrel to go down. In my opinion one of Slashes buffers is a good addition to a gun that you intend to run suppressed sometimes. Now, the question of using the adjustable GB with the suppressor, is another thing. I think that if You expect to be switching back and forth between suppressed and unsuppressed operation, you would do better with something like the Noveske switchblock or equivilant. this is an adjustable gas block that has different settings, it is not infinitley adjustable like the screw type, but can be quickly switched back a forth from suppressed to non suppressed settings. Keep in mind, if you plan to shoot different loads and bullet weights from your gun, and 100% reliability is required, along with possibly having to go longer than each range session between cleanings, as you might in a combat scenario, you're not going to want to fine tune your gas impulse down to the bare minimum as you might with a competition gun with a lightened bolt carrier, which I also would not suggest for a gun that you plan to run suppressed.

As stated above, the 6.8 ammo is going to be more expensive. Is your friend planning to reload, that might offset the ammo situation a little. The other thing, 6.8 will be a small platform gun while .308 will be a large. You know that it will be less expensive building a small platform gun than a large, but over time, the ammo thing will negate that. Question is, does he want a small platform gun or large? Also, I know the 6.8 will outperform the 300 BLK, especially if he want to shoot at 300yds regularly, but I'll bet the 300 would be cheaper to build and to feed than the 6.8 and i've pushed 125/135 gr .30 cal bullets to 2600 fps out of my 300 barrel, although I've not shot it past 200 yds.

As noted above, unless they were to come up with a new shorted receiver (not likely), Your looking at a 16 or 17" barrel. I think that to make the 9 lbs limit you might need to go with a CTR or equivilant and a light weight contour barrel. Based on the experiences of our members, it would seem that the CF barrel manufacturer's that I know of would have a tough time meeting those quota's. I guess if you built a test gun with a heavier barrel and weighed it, you'd be able to see how much (if any) weight needed to come off to meet the requirement. I would think that if accuracy was the goal, you'd like a heavy contour barrel if it would make the weight.

I think the heavier bullets (168/175) would be the better choice If your trying to feed multible guns, I wouldn't let what works best in one gun (FAL) dictate the choice for you.

Off topic here for a second, anyone know what brand mag that is in the SBR in the picture? The only translucent ones that I've seen are the Lancer's and I've got them. This one loooks different.

Unless your planning to use it as a dedicated long range gun, there is no reason for you to have a barrel that long. do you hunt at 1000M? If not that long barrel just makes the gun heavy,and clumsy, even without the can. I'd say 20" is a good compromise. Your not giving up any accuracy, just some muzzle velocity, as far as getting that back with the suppressor mounted, I'm not sure about that, but a suppressed gun does tend to have more cycling pressure, so I could see that back pressure possibly indicating higher bullet velocity.

I'm not clear on the last line of your last post, but, to address what I do understand. It is generally agreed that it's a good idea not to combine an Armalite bolt with a DPMS type barrel extension. I've switched the parts and manually cycled the action and the bolt closed, but have not and will not ever try to shoot the gun like that. the reverse also applys, don't use a DPMS type bolt with an Armalite type barrel extension. Now, as far as one gas system (Armalite vs DPMS) being superior, they are essentially the same. Most of us agree that a longer gas system (rifle vs mid/carbine) will give you a more reliable gun that kicks less, and is easier on bolts. The dispute between gas and piston can be involved, there are advantages and disadvantages to each. If your building your first gun I'd suggest you go with DI gas just because it's simpler, less parts, cheaper. Headspace is (please excuse if I don't use the proper technical language) the space between the surface that the cartridge rests against on the face of the bolt, and an established point in the chamber where the shoulder of the cartridge will locate. What we're concerned with here is that there is enough room in the chamber so that when a rd is loaded, there will be just enough clearance to allow the bolt to close without compressing the cartridge against the locating shoulder, but not enough to allow the cartridge to be able to move back and forth in a closed chamber with a stripped bolt. We're talking thousandths of an inch here 12 thousandths would be too much. If your asking what headspace is, your probably not ready to check it yourself, besides which you need specific GO/NO GO gauges. For your first one you'll do yourself a favor to have it checked by someone that has done it before, and has the gauges.

I forgot to mention, if you source your barrel and bolt/BCG from different people (not a custom made barrel fitted to a specific bolt) Your going to want to have your headspace checked before firing the gun.

As posted above, you've made some good components choices, to end up with (IMO) a gun that will be superior to what you might buy. In addition you'll have the satisfaction of putting it together yourself. The MA TAN receiver sets are excellent, fit and finish are top notch. As stated by Edgecrusher, You'd do well to match your bolt carrier group (or at least the bolt) type, to the barrel extension. You can build it as Armalite pattern with Armalite bolt and Armalite pettern barrel extension (I have done this, my MA TEN has a Armalite BCG and Noveske Afghan barrel) or DPMS pattern with DPMS BCG and a barrel with a DPMS pattern barrel extension. Two things, if you decide to go with an Armalite type rifle length gas sysytem, don't forget to use an Armalite rifle length gas tube vs the DPMS rifle length gas tube (Armalite will be 1/4" longer to match the slightly different Armalite gas block location) You will still need to order the Troy rail to match a DPMS rifle because the MA TEN upper has the 1.437-16" pitch DPMS barrel nut thread and not the 18 pitch Armalite thread.

Nice work on the rail, does your friend have a cnc mill?

How about posting some pictures of your mates custom made quad rails?