Zumabob JD Machine Build

[zumabob1957]

Nofail,

I keep forgetting to ask you about the Sacramento guy. You are in Sacramento do you know who I'm talking about ? Luis has the best booth. It a bit of a mess but he has good quality stuff. Its reasonably priced. Buy once

                                              Bob

[Robocop1051]

Luis has a store, sorta, in south Sacramento. It's more of a small room in the back of lawn mower repair shop.

He is the biggest dealer of Magpul parts, and his prices are more than fair. As long as you are only looking for mid-range quality or mil spec parts, Luis is your man. He makes the most of his business at the gun shows. I introduced a bunch of local LE to his shop. Since he is practically in the heart of the ghetto, a lot of cops stop by when they are on duty. He is just a few miles south of my beat, so I don't get to swing in as often.

[zumabob1957]

Yes well seemed to have had are bad luck with JDM but in the end they are very nice people and their products are pretty good. They also have to put up with the strict regs of California. I also had the no call back (not all the time) and saying one thing and doing another. But in the end I'm happy. I would refer them .

                                                      Bob

[NoFail]

Nofail,

I keep forgetting to ask you about the Sacramento guy.

You are in Sacramento do you know who I'm talking about ? Luis has the best booth. It a bit of a mess but he has good quality stuff. Its reasonably priced. Buy once

                                              Bob

No I'm not in Sacto, I'm in Fremont, east side of S.F. Bay.

[NoFail]

Nofail,

I have been playing with my 308 on & off today. I loaded the pmag with 10 rounds and cycled it by pulling the

charge handle and letting bolt slide forward. If I did it

quickly I could eject all 10 rounds. Sometimes 15-20% it would jam. I dont know if the bolt didn't have enough momentum or the round was getting stuck on the ramp. I say that because all the casing are scratched . Could I

have a mag problem ?

Bob, call out your upper parts for us, and your buffer & spring again. And who's ammo are you using? I'm still not clear about your bolt carrier. Is it the current DPMS offering? How many rounds have you fired so far? Also,

this is a good topic for you to post up in this  http://308ar.com/forum/dpms-lr-308-general-technical-discussion/  forum where you are more likely to run across people more experienced than me to help. Really I'm no expert. But still I'm thinking buffer/spring first, I want to know about your ammo you're using too. Where's Yamadawg? 

Bob I have a question. Do your Pmags slide in and out of (fall out) you JD mag well easily? I don't have any mags yet. The only one I have tried in mine is from my brother in law's SR25. It drags inside my JD mag well and you have to pull it out with some force. I'm praying nothing wrong with my lower there but have some Pmags on order. Went to gun show today only LR20 Pmags there dude wanted 30 for a blocked one, forget that!!!! I wanted to buy just one to test with today.

[392heminut]

No Fail, you can get the P Mags from Brownells for $19.99 each.

[NoFail]

heminut thanks i already ordered a couple from LWRC same price. If those work then I'll get more. I'm thinking that the SR25 mag just isn't good for my lower. By the way do you know how much bro in law pays for one fkg mag for his SR25? $100  :cookoo:  Maybe there is something about the mags from KAC that they are different spec  <dontknow>  but I hope.

[zumabob1957]

Thanks guys,

Nofail, I am using the buffer and spring that came with my Vltor butt stock. The ammo I'm using is Winchester 147 gr. , American Eagle 150 gr.  and Federal 168gr.

Today I was At the range that had an hour wait. There was 60 people waiting and over 40 shooting. So I had plenty time to scan the whole gun shop two to three time over. The salesman let me try a 10 round DPMS steel mag. Well to make a short story longer it worked worse than the pmags.

So again it would shoot a couple rounds and than the bolt wouldn't slam forward. Soon as I released the mag the bolt would go forward.

The DPMS mag fit snug and much tighter than the pmags. The pmag are a bit loose but seem to work better.

Back to ammo. The three brand and grains didn't seem to make much difference. Its interesting that the bolt moves forward when the mag is released. I well check out that section that you gave me.

                                          Thank You, Bob

 

[NoFail]

Bob, Slash's CAR-10 Buffer w/spring. $111.00

[Robocop1051]

About once a year this topic comes up, and it becomes very hard for me not to bad mouth JDM.

Without going into a rant, JDM has advised in the past that they test and build their rifles using C-Product magazines.

Again, I can't comment on their current production line. I will say that I sold my JDM because it wouldn't hold onto a PMAG.

What I don't understand is how a CNC company can make parts that vary so much in dimension. Some work fine, mothers barely pull through. Aesthetically I think their great guns. Functionally I have issues with their builds.

[NoFail]

Yeah well I knew I should have followed my heart for what I knew I really wanted. This always happens to me when I don't follow my heart  :'(

Why did JDM have to be at that fkg gun show  >:(

[zumabob1957]

Nofail,

My next thing is get a car-10 buffer spring. Thanks for sending me to the other site. Got lots of info there. Mobil 1 is very popular. I was at a Jiffy Lube on Saturday. Asked the tech if I could have a little bit of Mobil 1 if he had some. He gave about 4 oz. which he charged me for. I was charged for 6.2 quarts. He over charged by  me .1 oz. I hope you know I'm joking.

[NoFail]

Oh Oh Ohhhhh yeah i thought you going to say JDM over charged you  <lmao>

[zumabob1957]

Nofail,

I forgot to tell you how many rounds and about my Bolt carrier. I have shoot about 100 -120 rounds. I don't

t know much about my bolt carrier other than it cost 220.00 , black and heavy. I got from Luis.

                                                        Bob

[NoFail]

Nofail,

I forgot to tell you how many rounds and about my Bolt carrier. I have shoot about 100 -120 rounds. I don't

t know much about my bolt carrier other than it cost 220.00 , black and heavy. I got from Luis.

                                                        Bob

I don't know Luis. I'm not from Sacto.

Bob 100-150 rounds is not a lot, you are still breaking in.

Maybe that's all it is, but the CAR-10 is a good thing anyway, go with it.

[zumabob1957]

Nofail,

I'm going to  the Costa Mesa on Sunday. It makes more sense after going to that site you refer me to .

[zumabob1957]

Costa Mesa to the gun show and also talk to Luis about that quad rail.

[zumabob1957]

Nofail,

JD Machine called today want to ask me a question about my lower. What do you think is up? I well see him at the Costa Mesa show this weekend.

[NoFail]

Nofail,

JD Machine called today want to ask me a question about my lower. What do you think is up? I well see him at the Costa Mesa show this weekend.

Bob, I have no idea, except maybe about the mag well?

Fed Ex will deliver my two new LR-20 Magpuls today and I anxiously await their fitment test. If they are tight in my lower then JDM has issues. I know you said the LR-20 mags are not too tight in yours. But I am spooked that the KAC mags from my bro's SR25 are way fkg tight in my lower.

[zumabob1957]

Nofail,

JD  was no big deal.  It was a issue that was already taken care of.

I think your mags should work out fine. The Pmags where a little more loose than the steel mags.

You were right about my buffer and spring. Luis and Sal set me up with shorter buffer and a stronger spring. Now the bolt is completely out of the way of the ejection port. Monday I am calling Samson To take care of the quad rail. Luis agreed that it was defective.

I have a few thing to do until completed.

1. Ambi safety

2.Flashlight

3.Mount

4.Trigger

When are you going to be ready to take yours out?

Thanks for your help

   

                                          Bob

[NoFail]

Hi Bob, good going on getting a buffer and spring arrangement. I know that Slash's setup is very expensive so what you did is probably good enough.

I hired a gunsmith to lap the front end of my upper to make it perfectly perpendicular to the uppers bore. We had to have a special lapping tool made to accomplish this. On Monday night we use tool to lap upper and then install barrel, I am going to polish the lugs of my barrel extension today using dremmel tool, a few spots need to be cleaned up. But tomorrow night my upper will be 100% complete with a barrel that is as aligned with the upper BCG as it can be, thanks to the lapping.

I received Pmags yesterday and fitted them into he lowers mag well and they are not too tight in there so good. There is some wiggle in there though with the Pmags moving about 1/4" front to back if movement measured from bottom of magazine. I dunno if that is good or bad.

Now I have to wait for the scope I want. It will come available later. SWFA should do a group buy at another web site that I frequent, they may do it middle of April but when will they start to ship their new 1-6X scope? IDK hopefully by May, oh I hope so. So unless I get some other kind of sight package first I still have a wait. But this will give me time to collect lots of components for doing hand loads.

Besides all that I want a bi-pod and a sling and if the Pmags work good I get more of those. I think that should do it? I hope so.......

[Dusty44]

Tight or loose magazines is not what matters.  It is where and how the loaded cartridge at the top of the magazine is positioned.

Steel magazines work if the lips are adjusted properly,  which can be a good trick, and if the follower is moving properly within the mag.  PMags are molded so the lips are always adjusted properly and there are several other things about the molded shapes at the top of the mag which would be either impossible or very expensive to do with steel.  The followers in PMags are engineered to stay straight and level much better than most other followers.  (PMag followers are available separately for steel mags.)

AR style mags should be loose,  at least some.  The basic concept is that these mags would be used once in combat.  Press the release,  the empty mag is gone,  jam another loaded mag into place and keep shooting.  A location where there has been a combat firefight would presumably be littered with empty cartridge cases and empty magazines.

Tighter fits relate to private,  individual,  and competition use where proper fit and precision feed might relate to more precise shooting and to reuseability of the mags.

[zumabob1957]

Nofail,

I am anxious to get this thing firing and cycling. I wish I had the patients like some of you guys to collect all the part put it together all at once and brake it out. Down the line I'm going to upgrade the trigger, butt stock, buffer and spring. I am thinking of the Trijicon Accu-Point 1-4x24. I'm using A2 iron sights with a red dot. I can always throw my ACOG 4x32 even though its made for a .223/5.56. Tomorrow its going for a spin even though the hand rail is broken, which reminds me I have to deal with it Monday.

Are you really going to wait until you get your scope before you take yours out? I had planned to build mine in 8 to 9 months. Couldn't do it . Its has been 4-5 months.

I also bought a Vltor charge handle and a catch bolt release (like the Magpul B.A.D. part) and R.T.S. for my .223 I like the RTS enough to buy another set for the 308.

                                                        Bob

[NoFail]

It's just worth it to me to wait for what I want and I want this.    http://swfa.com/SWFA-SS-1-6x24-Tactical-30mm-Riflescope-P53845.aspx

Should be a decent group buy over at snipers hide coming up. SWFA offers kits with rings and mounts in their group buys so I'll be all over it. Still i haven't felt like buying any iron sights or other.

[zumabob1957]

That right, I do need to get a scope mount. Or I can duck tape it to the upper. They do make black duc tape. Haha.

                                                    Bob

Its never ending.