Semi auto build

[garandman]

For years I've tried building semi semiauto rifles myself… ARs, AKs etc.

Even with the precision builds I've only been able to get to a little bit better than 1" group at a 100 yd. Even with handloads. Same with my most recent…. a pinned and welded 14.5" AR15.. And it's no better than the rest.

Well I just got notified that my JP rifles Barrel is getting shipped and I'm wondering if I should take it to a professional builder or if it really is plug n play for a non professional "gunsmith" like me

It comes with a matching head spaced bolt. So theoretically that's taken care of… the question is ... is installing the barreland torquing the barrel nut that simple of a process ?

 

[The boogalorian]

Just built a seekins precision at in 6 arc for prs. 22” bartlein barrel from Craddock Precision.
Did a ladder with 105 Berger’s and was underwhelmed with the accuracy. Thought maybe it was me, or just semi atoms aren’t that accurate. Then tried a ladder with Berger 90gn bullets and wow. It’s a little slow right now but I haven’t found the upper limit.

 

[rckendall]

I've had similar experiences and am interested to hear the responses from others. When I went all in on an AR, I bought a complete Varmint upper from White Oak Armament. I recently went through the load development on it for 77 gn SMK w/ Varget, and I can say that it will shoot 1/2" groups at 100 yds shooting off from a Harris bipod and a bag in the rear.

One area that may play an important part of this, is the fit of upper to lower. Some Mil-Spec pieces fit up pretty loosely and give me doubts as to their chances of shooting well.

Good luck and I will be following this thread.
Richard

 

[Mark M.]

The Tack-Driving AR — Secrets to AR Platform Accuracy « Daily Bulletin

One Shooters' Forum member asked: What makes an AR accurate? What parts on an AR can really affect accuracy -- such as free-floating handguards, barrels, bolts, bolt carriers? He wanted an honest, well-informed answer, not just sales pitches.

bulletin.accurateshooter.com

 

[garandman]

One area that may play an important part of this, is the fit of upper to lower. Some Mil-Spec pieces fit up pretty loosely and give me doubts as to their chances of shooting well.

Makes sense. And I'm wondering if the Accu-Wedge helps.

 

[garandman]

The Tack-Driving AR — Secrets to AR Platform Accuracy « Daily Bulletin

One Shooters' Forum member asked: What makes an AR accurate? What parts on an AR can really affect accuracy -- such as free-floating handguards, barrels, bolts, bolt carriers? He wanted an honest, well-informed answer, not just sales pitches.

bulletin.accurateshooter.com

From the article.... This was my primary question....

3. True Receiver Face: We’ve found that truing the receiver face is valuable. Some may argue this point but it is always best to keep everything related to the barrel and the bore in complete alignment with the bore (i.e. barrel extension, bolt, upper receiver, carrier, etc.).

 

[Minshooter]

Precision is in the target of the beholder, but:

1. Most 14-1/2 (presumably M4 pattern?), carbine gas tube, etc. barrels, are doing very well to get to 1".
2. Anything less than the best trigger is going to compromise even the best barrel and installation.

 

[Sandstorm]

I have built several and the only one I got to shoot..really shoot was a 6.5 Grendel
with a X-Caliber barrel @ 24 inches and a Trigger Tech Diamond for Ar's.
Your JP...with a good Trigger...really good trigger might be the ticket.

Ps...and the right bullet.
And I used a Trued Viltor upper receiver.
Glued in place

JP rifles Barrel is getting shipped

 

[garandman]

Your JP...with a good Trigger...really good trigger might be the ticket.

Is a Geissele trigger, just over 2lb. A little heavy, but a super clean break. I'm a bit of a Clydesdale and like a heavier trigger for "action" riflles.

 

[Sandstorm]

I dont like any of the AR triggers....but the Trigger tech and Geissele are acceptable at best.
Its just real difficult to shoot well when your used to a Jewell at 2 to 3 oz

 

[Rodney]

I’ve built a few AR’s myself. Getting bolt gun accuracy is not easy to say the least, especially with the 223 cartridge. My best shooter in that caliber is a 24” varmint barrel 1 in 7 twist with a Wylde chamber. I’ve got the clamp type gas block and I did true up the receiver face. I’ve shot some sub MOA groups easily with 80 grain matchkings, and 80 grain ELD’s. Unfortunately this is done by single loading them due to OAL being to long for the magazine. Kind of defeats the purpose of an autoloader though. For magazine compatible rounds, a custom chambered barrel with the correct free bore would be the way to go I think. Of course even the correct free bore will not allow the bullets I mentioned above. I also have a 224 Valkyrie that shoots very well with the heavy 224 bullets at magazine length and is the way to go for extended range shooting with this platform. The 6.5 grendel is another good cartridge that I have and it shoots very well. You just can’t use the heavy for caliber bullets that have the high B.C. like you can with the Valkyrie. EGW sells the clamp type gas blocks and the free float front hand guards that are a good start for an accuracy build. Haven’t tried the 6 arc, but It sounds very promising. Good luck with your builds. You can build an accurate AR in your garage. One more thing, I use a reaction rod when torquing the barrel. Doesn’t put stress on the receiver.

 

[garandman]

I’ve got the clamp type gas block and I did true up the receiver face.

You can build an accurate AR in your garage. One more thing, I use a reaction wrench when torquing the barrel. Doesn’t put stress on the receiver.

This is what I need more info about....

 

[Sandstorm]

The Trigger tech I think with the adjustment gets down to under 2 lbs...I think
it closer to 1 1/2 lbs

 

[Pawnee Bill]

If you want a precision AR, send the JP rifles barrel back and then call Compass Lake Engineering and have them make you a Krieger barrel in the caliber of your choice.

 

[skeeljc]

Here is what I have found that affects AR-15 accuracy:

1. The fit of the barrel extension with the upper. JP Rifles uses a shrink fit where you heat the upper and then slip it over the barrel extension. Some use a Loctite compound to glue the barrel in. You can request an oversized barrel extension and machine it for a press fit.

2. The stiffness of the upper. Most AR-15 uppers are slimmed down to reduce weight. There are heavy wall uppers out there. DPMS makes a good one.

3. The lockup between the upper and the lower. You can ream the pin holes and install oversized pins. A set screw installed in the lower that pushes up against the rear lug of the upper will provide a good lockup.

My precision AR-15 with a White Oak 24" 1 in 12 twist barrel will hold sub 0.5" MOA.

 

[garandman]

If you want a precision AR, send the JP rifles barrel back and then call Compass Lake Engineering and have them make you a Krieger barrel in the caliber of your choice.

That's TOO precision. This will be a 14.5" P&W upper... just trying to avoid doing things that cause inaccuracy in this build.

 

[Liven The Dream]

AR's In Service rifle and Match Rifles shoot Big Scores out to 600 yards and More .
Parts are the Key Factor. Barrels and Triggers #1.
White Oak Sells Parts and Builds Winning Stuff.
Hand Load Quality Ammo with 69, 75, 77, 80 gr. and up Bullets.

Shooting a AR with Iron Sights ( Short Sight Radius ) is Difficult but do able.

I built a Match Rifle with White Oak Scope 1-8 Barrel Areo Upper and Lower all Mil. Spec Parts
LaRue reworked Trigger Scoped. This Thing has Cleaned a 600 yard F/Class Target at 540 yards ( Back Yard Range) more than once with 75 and 80 gr. Bullets .
The Guard Shoots AR-10's to 1000 yards very very well.

Bargain Barrels and Ammo may not Shoot Small ?

 

[itchyTF]

I built an AR10 in 6.5cm but haven’t shot it yet so don’t know how much of what I did will make a difference. I was told the accuwedge isn’t that good because it still gives. I used Devcon in mine.
I also used a .010 shim between upper and lower at the front pin. Not real convenient when taking it apart but didn’t like the slop. I also used a clamp on GB and trued the receiver. I used a shim between barrel extension and receiver. I tried using locktite to hold it on but to my surprise it didn’t stick at all.

 

[chutem]

This is what I need more info about....

Search Results

botach.com

This is what I use instead of vice blocks. Works great!

 

[DangerRanger]

I think you will be fine doing what you normally do, as long as you understand how to build an upper in general. I planned to bed and shim my compass lake rock creek. Mine was on an aero m5 enhanced reciever so trying isn’t really an option(handguard Mount is in front of reciever face). I decided to just toss it in there first and see what happens.

The rifle shoots so well I haven’t messed with it. Did nothing out of the ordinary for me aside from buying a clamp on gas block instead of set screw. An accurate gas gun is a blast. Good luck and have fun.