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Rebuilding an AR15, wheres the gurus?

Ive decided to rebuild my AR15... built it years ago, some thing just need upgraded, and or replaced. Gas block, tube seized up, started ejecting wrong and not fully ejecting, needs cleaned real well... Figured Id just go through the whole gun. Barrel still is shootin... its a satern cut rifled 24 inch Heavy contour.

Im thinking:

1. Jp adjustable gas block - JPGS-8D dentent adjustment

2. New rifle length gas tube - they all are the same right?

3. Seekins SP3R V3 Handguard

4. Seekins IRMT-3 V3 upper - thicker barrel tang, helps with the heavy barrel I have to flex less...



I have a stag lower, all aftermarket parts, geissle trigger, PRS stock, yada yada..

Would the seekins upper on a stag lower be a problem? would it still have that gap between that moves? Or would a matched upper lower machined for each other be better? Seekins dont have mached uppers/lowers thst I found, but I like that seekins upper...

Any opinions? Ideas? I got a lot of small parts Ill reuse... biggest things are gas block, tube, handguard, upper and lower that fit tight together...
 
You may try a can of carb and choak cleaner. When I was still in, if we could afford it we used to stick the straw in the gas tube and hose it out, then clean the barrel. If you just want an upgrade, sky's the limit. I don't know about Seekins fit. I run a PRI upper on my Stag lower and it's been a great rifle.
 
You might wish to see www.ar15.com, as well as the link cited above. I am not current with all the AR parts even though I have built one. My gas tube got plugged and caused loading and ejection problems, but cleared it and all seems well now. I took it off the rifle, held it upright, filled it with some kind of solvent, let it sit, and then blew it out with an air hose.

I do not find adjustable gas blocks necessary. If the gas port is right sized and at the right place in the barrel, a standard gas block should be fine. Mine is, and I have a 22" barrel. Note, barrel length has an impact on gas timing, which is of paramount importance to reliable cycling. I believe all rifle length gas tubes are the same. For a handguard, I got something small and simple from JP. I do not need all the rails. I used a Sun Devil lower and upper, but that was from pre-Obama days. It seems fine, holding a heavy Krieger barrel with a 0.930" muzzle on a 22" barrel. It is heavy. I am not sure the gap between upper and lower means that much. I have an adjustment for that on mine, but never used it, and it still has shot multiple 0.3" 5 shot groups at 100 yards off a bipod and rear bag.

I found that the barrel and the trigger are critical for accuracy. I use a Geiselle Match trigger. My Lyman trigger gauge says 2 lbs on stage 1, and then 8 oz on stage 2. It definitely helps. And DO follow through when shooting the AR.

More useful info on accurate ARs at www.6mmAR.com. This is an accuracy based forum, so my comments are to that end. My AR is not a tactical weapon. It is a 13 lb. tank (unloaded), built so I could see how accurate I could make an AR. Fun experiment. Oh, and do handload!

Phil
 
I am far from being a guru, but but I have done some upgrades myself. I went with a SLR adjustable gas block because it is designed with detents and the adjustment is on the front of the gas block. They send a long allen wrench that allows you to adjust the gas block from the front of the forearm and if you change ammunition you can just note the number of clicks for each one. It makes the gun shoot smooth and with a heavy barrel you will likely be able to see your bullet impacts. I have a JP adjustable that I don't use because it does not have detents and requires taking the forearm off to adjust the gas block - a pain for me. It also uses a set screw to lock the adjustment screw - another pain to me.

The Seekins upper looks nice, but I personally would opt for spending $71 more and buying a matched JP forged upper and lower. If you do mix upper and lowers and there is some slop (which I personally hate), then I keep shims on hand. http://proattach.com/nationalmatchshim.htm
 
You might wish to see www.ar15.com, as well as the link cited above. I am not current with all the AR parts even though I have built one. My gas tube got plugged and caused loading and ejection problems, but cleared it and all seems well now. I took it off the rifle, held it upright, filled it with some kind of solvent, let it sit, and then blew it out with an air hose.

I do not find adjustable gas blocks necessary. If the gas port is right sized and at the right place in the barrel, a standard gas block should be fine. Mine is, and I have a 22" barrel. Note, barrel length has an impact on gas timing, which is of paramount importance to reliable cycling. I believe all rifle length gas tubes are the same. For a handguard, I got something small and simple from JP. I do not need all the rails. I used a Sun Devil lower and upper, but that was from pre-Obama days. It seems fine, holding a heavy Krieger barrel with a 0.930" muzzle on a 22" barrel. It is heavy. I am not sure the gap between upper and lower means that much. I have an adjustment for that on mine, but never used it, and it still has shot multiple 0.3" 5 shot groups at 100 yards off a bipod and rear bag.

I found that the barrel and the trigger are critical for accuracy. I use a Geiselle Match trigger. My Lyman trigger gauge says 2 lbs on stage 1, and then 8 oz on stage 2. It definitely helps. And DO follow through when shooting the AR.

More useful info on accurate ARs at www.6mmAR.com. This is an accuracy based forum, so my comments are to that end. My AR is not a tactical weapon. It is a 13 lb. tank (unloaded), built so I could see how accurate I could make an AR. Fun experiment. Oh, and do handload!

Phil


Mines a tank too for accuracy. And it has prooved itself to be already. Just wanting to take it all apart clean it well and may as well re assymbol with some new parts for fun and to see if I can squeeze something more out of it..
 
The Seekins upper looks nice, but I personally would opt for spending $71 more and buying a matched JP forged upper and lower. If you do mix upper and lowers and there is some slop (which I personally hate), then I keep shims on hand. http://proattach.com/nationalmatchshim.htm

Good info.

The reason Im leaning hard on that seekins is the design of the upper... it has a really beefed up front end where the barrel attaches. With my 24 inch heavy bull, i can visually see the thin type uppers like are most common flex. Also the handguard doesnt attach to the barrel nut, it attaches to the outside of the receiver so i would get that receiver flex.

The weakest part of most uppers is where the barrel goes in and the barrel nut goes on. Its THIN aluminum. And it has a lot of weight hanging off it. Its just my opinion but I see this seekins design as an exceptional improvement, and especially in my case as most people dont run a 24 inch heavy barrel on an AR. Ive noticed I can shoot the difference in the flex and had fliers because of it. A receiver flex test can be done easily by putting a bipod on the front. Load oup 1 bipod leg only and shoot, you will get a poi to the left or right depending on which bipod leg had pressure.

Something ive noticed in the past and just happenes to find this seekins receiver that was made to deal with this type problem..
 
Check out Sasquatch in Grant's Pass Oregon. Call the Armory
Machined upper n lower piston operated if you want. Around $1450 complete. Gas blocks are low profile/adjustable
They credit you back on parts you dont want/need as per our last conversation.
They'll put on whatever barrel you want and set headspace so your upper would come to you complete.
Nice shooters.
 
I just built an ar upper similar setup as yours... ish custom lilja 22” barrel with 223 Wylde camber head spaced off bolt I supplied. My advice would be to eliminate the adjustable gas block, you can do so much more, so much easier with bcg and or jp silent capture spring, you can add and remove weights, and strength of spring. I did a jp upper matched with lower, sold the handguard bc I don’t care for their round tubes that they come with.... bcm makes probably the best upper there is as far as normal uppers. Lots tighter fit on barrel extension, zero slop, almost have to tap it in with rubber mallet. I like the seekins handguard but I wanted the longest I could get for shooting off a bipod, further away makes it more accurate, settled on 17” lone star I think. Full pic rail on top was important for me or would have gone with colbalt kenetics. They have a sick stock too. Might check it out. I build a few a year let me know if I can help.
 
One more Vote for White Oak ( have a Barrel in the Mail Now ).
Adjustable JP gas Block ? have seen trouble ?
My Upper is more Match/Hunter style. 15" M-Lock Hand Guard , Std. Gas Tube M4 Ramps .

Good Luck
 
One more Vote for White Oak ( have a Barrel in the Mail Now ).
Adjustable JP gas Block ? have seen trouble ?
My Upper is more Match/Hunter style. 15" M-Lock Hand Guard , Std. Gas Tube M4 Ramps .

Good Luck
I am not very knowledgeable about ARs other than the fact that I shot Hi-power matches in Michigan in the fall and winter. My AR ejected fine during warmer weather but once it got cold the bolt wouldn't lock back when the rifle shot the last round. We figured that the powder charge (Black Hills blue label) was too low for cold weather here and I changed the bolt latch also. This solved my problem. I'm not bad mouthing Black Hills ammo, it shot great (Half MOA) it just didn't have enough energy to cycle the bolt to the locked postion when it was cold. Make sure your rifle is clean and I use a very light lube too. I hope that this helps.
Darryll
 
John Holliger of White Oak Armament is one of the top, if not top civilian Service Rifle shooter. John is a friend and he is just a great honest guy. One I received from him in April.
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Legal Service Rifle and it shoots very well. I do my own bolt rifles, but leave the AR to the expert.
 
Dpms sportical upper.
True slickside and plenty of metal for your heavy barrel.
Or a mega arms HD even better but hard to find nowadays.
 
Sounds to me like it needs a tear down and full clean , probably just crud under the ejector or a weak spring... The AR is a filthy beast but will run if you run them wet till their so nasty you can't believe it.... But eventually you need to disassemble certain things and get in there with dentist picks , tooth picks , whatever... The long pipe cleaners for the gas tube run through occasionally won't hurt anything either , cleaning inside the BCG were it carbon up is necessary.... Maybe new gas rings...

As far as upgrades , well there's plenty , some good , some pure crap in my opinion... The adjustable gas block is good if you're running a suppressor or cheap ammo... My deal is I like a high quality bolt , BCM makes some nice ones...Other than that the sky and your wallet are the limit... Just be careful and do your research because there's alot of kool-aid out there and some of it will make your rifle less reliable than stock... As far as the gap between the upper and lower you can get a matched pair but it doesn't bother me , it will always have some , I am though shooting iron sights and not competition and half blind...
 
White Oak barrels are made by Wilson. They are fine and I use their 26 inch one on my personal AR. I would suggest you look at the Mega Arms side charge upper and the Young Manufacturing side charge bolt and carrier. Rainier Arms has the stuff.
The Mega Arms upper is thick and beefy and if you've never used a side charge you will wonder why they ever made it the way they did.....going to a side charge set up is T.H.E. first thing I do to any Ar I intend to keep.
Speaking of Kool-Aide...adjustable gas blocks are something I have never seen the need for. I wouldn't exactly go so far as to call the system "self cleaning" either. Somebody is going to have to offer up a better reason other than "but...but...you can dial down the pressure". So what, the system is designed to bleed off excess gas pressure and send it right out the side of the bolt carrier and so it does just fine. I have yet to see any parts "pressure beaten" on an AR. As far as for suppressed, it's a half measure at best...in my experience you really want a top of the line piston drive for that.
Speaking of gas blocks...any one else ever notice that absolutely every photo you see in a magazine of some dude shooting an AR he has his forend hand wrapped around the gas block area??? What is holding the front of the rifle all the way up at the gas block supposed to do for you??? I mean, other than burn your hand.....reminds me of a dope dealer holding his "nine" sideways.
 
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Honestly for the price of a precisuon upper the robert whitley uppers are decently priced for a precision rig, same amount of money as if you buy the parts and build something...

Ive thought about side charging uppers, but then id have to buy a new bolt too. My BCG is all fine... no reason to throw it to the side..
 
White Oak barrels are made by Wilson. They are fine and I use their 26 inch one on my personal AR. I would suggest you look at the Mega Arms side charge upper and the Young Manufacturing side charge bolt and carrier. Rainier Arms has the stuff.
The Mega Arms upper is thick and beefy and if you've never used a side charge you will wonder why they ever made it the way they did.....going to a side charge set up is T.H.E. first thing I do to any Ar I intend to keep.
Speaking of Kool-Aide...adjustable gas blocks are something I have never seen the need for. I wouldn't exactly go so far as to call the system "self cleaning" either. Somebody is going to have to offer up a better reason other than "but...but...you can dial down the pressure". So what, the system is designed to bleed off excess gas pressure and send it right out the side of the bolt carrier and so it does just fine. I have yet to see any parts "pressure beaten" on an AR. As far as for suppressed, it's a half measure at best...in my experience you really want a top of the line piston drive for that.
Speaking of gas blocks...any one else ever notice that absolutely every photo you see in a magazine of some dude shooting an AR he has his forend hand wrapped around the gas block area??? What is holding the front of the rifle all the way up at the gas block supposed to do for you??? I mean, other than burn your hand.....reminds me of a dope dealer holding his "nine" sideways.
I feel the same way about gas blocks , if the gun is gassed correctly ( gas port size ) it will bleed pressure off on its own... I am no fan of piston drive guns in the AR platform though... The old gas system will work just fine....
 
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Honestly for the price of a precisuon upper the robert whitley uppers are decently priced for a precision rig, same amount of money as if you buy the parts and build something...

Ive thought about side charging uppers, but then id have to buy a new bolt too. My BCG is all fine... no reason to throw it to the side..

Robert Whitley made the most accurate upper i ever owned.

arturbo40_zpshbfijds6.jpg
 

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