9mm AR bolt and buffer setups

Geerubb

Geerubb

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What are you guys running for your BCG and buffers in your 9mm AR builds? I currently have a pistol build that has the KAK extended heavy buffer, AR carbine spring, and New frontier modular bolt.

It runs fine on the factory ammo and near factory reloads that I put through it.

I just picked up a 16" so I can shoot matches (steel challenge and possibly USPSA) with. It has a Taccom ULW system (buffer, spacer, spring) but no BCG. Any body have experience with this setup? If so, is there a special bolt I should be running? Feels like the light buffer will beat up the gun a bit.

If the lightweight setup doesn't work, which bolt would I need to run a JP/Armaspec/etc captured setup? I dont think my modular one will work, because you have to remove a part for the captured spring to work.
 
I've been running a KAw Valley bolt and this buffer from Blitzkrieg

http://www.blitzkriegcomponents.com/ProductDetails.asp?ProductCode=RB5007

After breaking "gas keys" off of 2 bolts with a standard 9mm buffer and spring, this new setup is the bee's knees.

Edit: I'm running a 10.5" SBR with dirt cheap 115gr steel ammo. Although, this setup also runs 124 and 147 handloads just fine.
 
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I have never heard of people using an ULW buffer for a 9mm AR.
They usually use heavier ones. 9mm is blowback operated.
I believe the ULW set up is designed for adjustable gas systems in 556 and other gas operated ARs.
Because you can adjust the gas down, you can use a lightweight buffer and BCG.

Wouldn't be the first time I was wrong though, lol.
 
I picked up a PSA bolt for the Glock style lower. Worked too good. The spring in the bolt was weak and when I pulled the trigger twice I emptied a 30 round magazine. Changed out the firing pin spring and never had another issue. Wished I keep that spring or bought another bolt.
 
When I bought my Shockwave brace, I got the package that included the tube, 9mm buffer and spring. I decided to take a chance on it and was prepared to buy something else if it didn't run reliably. It has ran perfect so far both suppressed and not with 115's and 147's. The package came with the non extended buffer, so I ended up putting a bunch of quarters in the buffer tube to stop the excessive bolt travel. I have a 8.5" faxon firearms barrel with QC10 upper, lower, and bolt.
 
If you are buying a bolt...I strongly recommend the 1 piece bolt. Meaning, the "gas key" is machined as part of the bolt and not bolted on like an AR15. That is the single most frequent point of failure for these blowback operated guns.
 
Tim said:
If you are buying a bolt...I strongly recommend the 1 piece bolt. Meaning, the "gas key" is machined as part of the bolt and not bolted on like an AR15. That is the single most frequent point of failure for these blowback operated guns.
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Any examples of that?
 
I misread your first post - I see what you're saying now. That's easy enough to check.
 
Also make sure that your bolt/buffer/tube combo only let's the bolt barely clear the bolt hold open stop. The added mass of a 9mm will break them if the go too far (momentum)

Quarters work as spacers
 
Slacker said:
Taccom is doing a one piece still.

Fwiw, the cmmg bolt I have has held up really well to a very high round count.
I'd buy another.
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Is the Taccom or cmmg bolt compatible with the captured springs (jp, armaspec, etc)?
 
Based on what I have heard from Ryan (Slacker), you'll want to follow his advice. Not saying others on here don't have great experience too, I am just unaware of their knowledge.

I am hopefully going to start experimenting with my ultra short setup soon, which will be a CMMG bcg, a Phase5 Hex Pistol tube (short version), and the JP 9mm Silent Capture setup designed for the Maxim CQB stock kit.
 
Bought a complete JSE upper that came with BCG. Not 100% sure what it is. Using the Hahn Precision sub caliber buffer (and dedicated mag block).
 
Slacker said:
Dale, would you say the SCS system has less "bolt bounce" and shoots flatter than your old heavy buffer setup?

It was immediately apparent to me with my setup.
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I would say it shoots with less bounce, definately flatter.
 
I now have a Blitzkrieg hrdraulic buffer with a JP rifle spring. I like it. I have JP SCS , Blitzkrieg as well as a Slashes heavy buffer, so if anyone wants to try before you buy, contact me.
 
dbracin said:
I now have a Blitzkrieg hrdraulic buffer with a JP rifle spring. I like it. I have JP SCS , Blitzkrieg as well as a Slashes heavy buffer, so if anyone wants to try before you buy, contact me.
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I just installed my Blitzkrieg, but I used a PSA AR-10 carbine buffer spring. After some research the AR10 rifle spring is good for factory loads, but I shoot 135 PF so the carbine was suggested. Initial impressions are that it shoots much softer, will see how reliability plays out.
 
I posted this on another site.

My tests so far. This is just MY opinion.

I'm testing a 9QT heavy buffer and a Blitzkrieg right now. Both of these are way better than the JP 9MM SCS. When I was using the SCS the gun felt like it was beating it self to death, especially when the bolt would slam forward.

My completely un-scientific results.

First test is done.
JP SCS vs 9Q-T w/Wolf XP spring
Huge improvement with the 9Q-T buffer over the SCS. It's a much smoother and much softer shooter now.

Second test is done.
9Q-T w/Wolf XP spring vs 9Q-T with carbine spring
Gun functions better with the carbine spring over the Wolf XP. Smoother because the bolt is not slamming forward as hard as with the Wolf XP. Also easier to keep on target.

Each test was with 100 rounds of Speer 147 gr. ammo and shot out of a 7.5" QC10 barrel with an Omega 9K suppressor.

The next test will be the 9Q-T with the carbine spring vs the Blitzkrieg Hydraulic buffer and tuned JP 308 spring but it'll be awhile because I broke my wrist and can't shoot for the foreseeable future.
 
Ok so I am using the JP SCS 9mm for the Maxim stock in a LWRC Ultra Compact setup with 4 quarter-sized nylon washer spacers. Shot it with both my 4.5" barrel upper and 8" upper and it ran flawless for 200 or so rounds. Smooth, little rise. I'll do a write up this week if I get time but it is the truth.
 
Slash's 9-Q heavy extended 9mm buffer and I think I'm also running a wolf extra-power spring in mine with SIG brace. Runs like a top with 115gr and 147gr.
 
Rs1200xl said:
I just installed my Blitzkrieg, but I used a PSA AR-10 carbine buffer spring. After some research the AR10 rifle spring is good for factory loads, but I shoot 135 PF so the carbine was suggested. Initial impressions are that it shoots much softer, will see how reliability plays out.
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Update: Shot about 200 rounds Sunday in the Toys for Tots match. Recoil is noticeably reduced; I won't say the gun is MPX level, but it does shoot very flat with quick follow up shots. Aside from a trigger issue(hammer follow due to pin walk) and a light round I would say the reliability is really good. See the T4T thread under competitions for a FPV of shooting/recoil.
 
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Update: ran an additional 350 flawless rounds with the blitzkrieg buffer. Bumped the powder load up a few grains and it actually seems to have helped with recoil management. ~200 rounds at PGR Holiday Hosefest went great too.
 
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I’ll have to go back and swap them again one day just for fun, but I took out the 9q-t and installed the JP SCS. Changed the spring on Slacker’s recommendation, but now I don’t remember which one it is.
 
I just ordered one of the Taccom adjustable recoil systems with the cushion. I’ve heard only good things about how smooth they are. Interested to see how it works in my 10’5” SBR setup.
 
hlpressley said:
I just ordered one of the Taccom adjustable recoil systems with the cushion. I’ve heard only good things about how smooth they are. Interested to see how it works in my 10’5” SBR setup.
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Don't forget to update when you do. I'm sitting on the fence between that and the Blitzkrieg. Need to stop messing around and get it ordered.
 
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Saw this on Enos forum. PSA has released some photos of their Gen 3 bolts. Gas key is now machined as a 1 piece design and the weight is central to the BCG. Sort of interested as I've been worried I'd lose my key one of these days at a match. Hoping pricing isn't too bad.
bolts.jpg.f23e11d833703b4917ba427163ac271b.jpg
 
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Just to point it out:

Some folks in this thread are making recommendations for a 9mm buffer setup to run suppressed, and some are recommending setups for USPSA style shooting.

Just be sure to take into account the posters platform. The suppressor adds a bunch of back pressure in the blowback, A lightweight setup like the JP SCS isn't designed for that.

Right tool for the job etc.
 
Update on the Blitzkrieg buffer:

I've run it for about 1500 rounds and found it to be really soft shooting, however yesterday I noticed a bit more recoil than I had seen before. I did a tear down today and found the buffer to have very little hydraulic resistance when in the horizontal or 12 o'clock position. I've sent Blitzkrieg a note hoping to have this fixed under their 10 year/1million round warranty. Will keep everyone updated.
 
Rs1200xl said:
Update on the Blitzkrieg buffer:

I've run it for about 1500 rounds and found it to be really soft shooting, however yesterday I noticed a bit more recoil than I had seen before. I did a tear down today and found the buffer to have very little hydraulic resistance when in the horizontal or 12 o'clock position. I've sent Blitzkrieg a note hoping to have this fixed under their 10 year/1million round warranty. Will keep everyone updated.
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Forgot to update. But they sent me a new buffer within a week, great customer service. Ready to roll for SC state match.
 
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Rs1200xl said:
Forgot to update. But they sent me a new buffer within a week, great customer service. Ready to roll for SC state match.
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Still happy with this setup?

I’m looking to give my rifle a little less bounce.
 
Bought and installed the Blitzkreig buffer, and after 100rds or so, I didnt feel much of a change. Studying the video it looks like the barrel levels it self off better and gets back on target faster with less bounce.

The rubber on the standard buffer was breaking down and making a mess in the tube. Glad I found this thread.

left side is BK, right is standard

 
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Update for this old thread.

I'll keep this short.

I used a JP 308 spring with the 9Q-T and the Blitzkrieg 9mm hydraulic buffer. My AR9 has a QC10 7 inch barrel with an Omega 9K silencer. I shot 120 rounds of Speer Lawman 147 gr. ammo.

The first 60 were with the 9Q-T. There was not much recoil at all. The gun stayed flat and rapid fire shots would be pretty close on target. It was great!

The next 60 were with the Blitzkrieg. There was a little sharper feeling of recoil with the Blitzkrieg, the gun still stayed flat and did just as well on rapid fire as the 9Q-T. But the bigger difference to me was that the gun felt a lot lighter with the Blitzkrieg. I noticed it as soon as I picked it up.

The Blitzkrieg also ran some crappy Freedom Munitions ammo that wouldn't cycle with the 9Q-T.

So, for me the Blitzkrieg is the choice.

If you don't mind the additional weight, the 9Q-T is a little softer on recoil.

I want to remind everyone there is no hard science behind these tests, just my perception.
 
Butter said:
Still happy with this setup?

I’m looking to give my rifle a little less bounce.
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Sorry I never responded to this, been a little tied up and shooting was not high on the list. I just had failure #2 last night practicing for the NC match, this was a new failure to me. I felt more gas on my face(still running accurate with fast splits). When I was putting my gun away I noticed a rattle and found buffer in two pieces. The buffer only had about 1k rounds through it. I read of one of the top guys switching to MBX due this same failure a couple times, once at a major.

Emailed brian at blitzkrieg last night as we have talked back and forth before. I could probably do a repair on it, but I don't feel comfortable running a major match with a band aid. Hope I can get the replacement by Thursday, if not I'll be running the NC match in limited...

20180907_182616.jpg
 
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Rs1200xl said:
Sorry I never responded to this, been a little tied up and shooting was not high on the list. I just had failure #2 last night practicing for the NC match, this was a new failure to me. I felt more gas on my face(still running accurate with fast splits). When I was putting my gun away I noticed a rattle and found buffer in two pieces. The buffer only had about 1k rounds through it. I read of one of the top guys switching to MBX due this same failure a couple times, once at a major.

Emailed brian at blitzkrieg last night as we have talked back and forth before. Hope I can get the replacement by Thursday, if not I'll be running the NC match in limited...

View attachment 73530
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Ill ship you mine if you want or I can bring it with me, I shoot Friday morning
 
Butter said:
Ill ship you mine if you want or I can bring it with me, I shoot Friday morning
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Thanks for the offer, I'm scheduled to shoot Saturday morning. I'll think about, but with the forecast of rain I may just use the limited gun so I don't have to worry about damaging my red dot.
 
Happy to report I continue to shoot my AR with a 4.5" barrel, 8.5" barrel, and 16" barrel with all sorts of quality and shit ammo and it runs like a top...until the Remington UMC gets it too dirty! But seriously, now that I have my JP silent capture setup on it, I'd trust my life to the gun. Can't wait to see how they all run with an Omega 9K on the end!
 
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