AR-15 BS Thread

Just bought all the barrel parts for my retro a1 slickside build. 20" pencil barrel with 3 prong flash hider and triangle handguards. Now just need to figure out how to reliably mount my colt sp1 upper with the big takedown pin holes to my milspec lower. Any suggestions?

 

http://blackrifleworks.com/ar15-accessories-colt-large-hole-upper-receiver-offset-bushing-p-352.html

 

Manually chamber a round, fire, case ejects, doesn't chamber the next round. With 556, I can go through a magazine no problem, just no bolt hold open. With 223, fires first round, then either stove-pipes or ejects then does not chamber the next round.

Trigger springs are properly installed.

 

Sounds like the gas port to me I had the same problem with my .308 AR I ran it for a while and as I ran it it slowly worked better for me. When I was building mine in a class we had some guys with gas ports not quite big enough that would do the same thing, they worked fine when they were enlarged

 

Others have said the same thing. The manufacturer claims a gas port size of .092 which, from what I read, is fairly large. If it is a gas port issue, why do you think I could get it to function with 556 using a heavier H2 buffer when it wouldn't function with a standard carbine buffer? I'm wondering if it might be an extractor problem. I'm going to get the BCG out of my son's rifle and try it in my pistol to see if that fixes the problem. Sorry I've beaten this to death guys....

 

I fought with my .308 for a few weeks, also try making sure you have good alignment on your gas block and gas port, it might be just a little off and that could cause problems.

 

Is your gas block steel or aluminum? Maker?

If the gun didnt cycle with a car buffer the heavier H2 buffer would not work as it is now.

What length is the gas system?

I have a similar setup and problem. My barrell is a 10.5 in 1:7 carbine length gas system medium profile. But my gas port is .0725 in. Same lower, lpk and a psa blem upper.

Who makes your upper?

 

Looking for opinions on the POF USA p415 or the new POF Puritan P15 entry level model. Both are piston rifles. I am new to ARs and this will be my first. Tge p415 is a bot out of my budget at around $2500 but the puritan looks like a pretty suped up "entry level" AR for around $1400

 

It's a Radical Firearms upper, carbine length system. I honestly don't know if the gas block is steel or aluminum. I had it almost all torn apart yesterday to see if I could find anything obvious. When I checked the gas key I was surprised that I was able to tighten the two allen screws. I then did a better job staking them both down. I didn't want to take off the gas block since I've never done that before and wanted to try everything else first. Was planning on taking the bolt out of my son's gun to see if it ran better with it...then I remembered he has a piston gun so that won't work..

 

if the gas block is off a little bit it will cut the gas going to the carrier causing you to have basically a single shot rifle. I would pull the gas block and try to remount it. it isn't that big of a deal. especially since it is a screw on gas block.

 

So I had an issue that was directly due to an aluminum gas block.

Aluminum and and AR's don't mix when it comes to gas blocks. They start opening up due to heat and allow gas to escape.

If you have a magnet you can simply put it on the gas block and if it sticks its still if it falls off it's not steel and likely aluminum.

However the issue with your BCG being able to tighten the hex screws is more than likely a major problem.

Swapping out the BCG would help you solve for that.

If that is the issue, send yours back to AIM and get a new one. Don't screw with it.

 

Don't know much about POF. But on piston guns. Most companies uses proprietary parts on their guns.
If I went piston I would get a lmt upper, to match my lmt Lower or get a PWS rifle.

 

I'll have to check and see if my gas block is aluminum, that could be my issue.

 

I'm getting ready to throw a few more parts at my AR build. I have an assembled lower (no stock kit) and an upper with just the basics (dust cover and forward assist), a 16" carbine barrel and that's it. I'm thinking of adding the following:
Magpul MOE trigger guard
Bravo Company low profile gas block
Yankee Hill 12" diamond series rail
Magpul MOE rifle stock kit
Gas tube
Upper action block

Holding off on the BCG for now

thoughts, any of the parts I'm thinking about just complete junk or incompatible?

 

I'd like to have a collapsable stock but MA says it would make my rifle evil. I do have a threaded barrel, just thinking about thread protectors initially but would like to put a Bravo Co compensator eventually (can't have a flash hider either). The added accessories and optics will come later, I'm just giving the build a little push (it won't even have a BCG so I won't even be able to fire it). I'll get BUIS initially since it's a flat top, get comfortable with them, then go with some sort of optic or red dot.

My lower is pretty well built IMO, it has a Timney trigger, KNS pins (I know I'll never NEED them but what the hell, right?), B.A.D. lever, Ergo grip and the rest is Rock River Arms.

 

Sighted in my dissy yesterday for a 50/200. Realized my fsp is slightly canted to the right. Whatever, it's zeroed good enough for me.

 

http://store.fourguysguns.com/collections/frontpage/products/dealer-clearance-special

250 for an Adams arm piston kit with barrel.

 

Blackhawke88, did you order the bushing or find one locally?

 

I'd really like an AR, but I also love the M1A. Would like to get one in a few months, not sure which way to go. I like the M1A more, but the price is whats killing me on it.

 

Edit whoops