Which Ar-10 BCG?
- Thread starter Jamesr1
- Start date
I have had good luck with JP and Toolcraft.
The JP was expensive but nice and I bought it during one of the gun ban scares of the Obama administration so oddly it wasn't that much more expensive than a DPMS parkerized BCG.
The Toolcraft BCGs look every bit as nice as the JP but cost a lot less and you can get NiB coating instead of nitride.
The biggest thing to worry about is firing pin size.
My JP is a "standard pressure" bolt and I have never had problems with large rifle primer ammo.
I have never tried small rifle primer ammo with that bolt but evidently that can lead to pierced primers.
I have also heard the opposite, that high pressure bolts can pierce large rifle primers.
In my opinion, brass life in AR ammo reloading is quite a bit shorter because of how much it needs to be resized after every firing so spending money on a high pressure bolt so you have to spend more money on small rifle primer brass that probably won't let you increase your brass life or operate at a higher pressure accuracy node is kind of a waste.
Basically be skeptical if anyone tells you that you "need" a high pressure bolt.
The JP was expensive but nice and I bought it during one of the gun ban scares of the Obama administration so oddly it wasn't that much more expensive than a DPMS parkerized BCG.
The Toolcraft BCGs look every bit as nice as the JP but cost a lot less and you can get NiB coating instead of nitride.
The biggest thing to worry about is firing pin size.
My JP is a "standard pressure" bolt and I have never had problems with large rifle primer ammo.
I have never tried small rifle primer ammo with that bolt but evidently that can lead to pierced primers.
I have also heard the opposite, that high pressure bolts can pierce large rifle primers.
In my opinion, brass life in AR ammo reloading is quite a bit shorter because of how much it needs to be resized after every firing so spending money on a high pressure bolt so you have to spend more money on small rifle primer brass that probably won't let you increase your brass life or operate at a higher pressure accuracy node is kind of a waste.
Basically be skeptical if anyone tells you that you "need" a high pressure bolt.
+1 on the Toolcraft. I bought the 6.5 marked bolt with the dual ejectors. Not sure if that was needed, but it sure does throw the brass!
Toolcraft 6.5 Creedmoor Double Ejector BCG
Toolcraft 6.5 Creedmoor Double Ejector BCG - dual ejectors add reliability to your AR with consistent, powerful ejection. The largest Toolcraft dealer!
www.armorally.com
That has the small firing pin, any issues?
+1 on the Toolcraft. I bought the 6.5 marked bolt with the dual ejectors. Not sure if that was needed, but it sure does throw the brass!
Toolcraft 6.5 Creedmoor Double Ejector BCG
Toolcraft 6.5 Creedmoor Double Ejector BCG - dual ejectors add reliability to your AR with consistent, powerful ejection. The largest Toolcraft dealer!www.armorally.com
[QUOT
No problems so far. Once I got the gas block tuned, which didn’t take long, it has been 100%. This is only 3 shots on my ladder test
Attachments
What is enhanced?
I like NiB, DLC and nitride finishes on a BCG because they are easier to clean and more tolerant of dry running. Some AR15 bolts are enhanced with better geometry on the bolt lugs to reduce stress concentration and cracking. I don't think any of the AR10/LR308 BCGs do that.
I like NiB, DLC and nitride finishes on a BCG because they are easier to clean and more tolerant of dry running. Some AR15 bolts are enhanced with better geometry on the bolt lugs to reduce stress concentration and cracking. I don't think any of the AR10/LR308 BCGs do that.
Toolcraft or JP; if I were balling on a budget I’m going for the toolcraft, if no budget then the JP it is. Either one be sure to make sure you get the bolt head spaced to your barrel extension.
The LMT dual ejector bolt gives ejects brass twice or maybe even three times as far as a single ejector bolt, at least in my eceperience. The LMT also has a captive firing pin retainer and is chrome plated.
JP is where it’s at for me. I’ve has issues with a couple others, nothing terrible, just not as reliable when cycling. Switched to the JP full mass and my 6.5 AR hasn’t jammed since.
My two cents, I’m sure it’s just the combo of parts, my rifle didn’t like the Aero or toolcraft, who knows. But she’s super smooth now so I plan to run JPs in all my future builds.
My two cents, I’m sure it’s just the combo of parts, my rifle didn’t like the Aero or toolcraft, who knows. But she’s super smooth now so I plan to run JPs in all my future builds.
No doubt a JP or LMT will be great but for 1/2 the price the Toolcraft small firing pin has been 100% fine for me, top group is a different gun.
Compass Lake Engineering uses Aero Precision bolt carrier groups and their AR10 uppers shoot bug holes. I had them spin a Bartlein 6.5 for me and he did recommend a jp high pressure bolt for the 6.5 . Which is what I used. However I have a 6.5 Brux build that has a toolcraft high pressure bolt and it runs just as well. Never had a. Issue with any toolcraft in AR10 or ar15
I've had good luck with JP bolt carrier groups in big frame rifle projects. FMOS in 6.5 CM and LMOS in .308.
There's no reason not to opt for the high pressure bolt.
Both Proof Research and Craddock Precision use JP bolts to headspace their AR' format barrels. Reason - They're all well under a thou' in tolerance.
There's no reason not to opt for the high pressure bolt.
Both Proof Research and Craddock Precision use JP bolts to headspace their AR' format barrels. Reason - They're all well under a thou' in tolerance.
Did you have any noticeable difference in the recoil impulse between the two? I have been debating between getting the FMOS vs. the LMOS for my 6.5 build.
I've never used the LMOS (low mass) system in the 6.5 CM, since I firmly believe the 6.5 CM needs the FMOS (full mass) bolt carrier to function optimally.
I have used both in the .308 and much prefer the LMOS with the right spring and buffer plus of course an adjustable gas block.
I have used both in the .308 and much prefer the LMOS with the right spring and buffer plus of course an adjustable gas block.
I just ordered a chrome plated BCG that looks like has good specs for the price. I'm sure it will turn into another rifle at some point. Here's the link if anyone might be interested: https://www.peacegeek.net/product-p/a-0002.htm
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I run a Lantac in my 6.5CM AR. Can’t say it’s better or worse than anything else, but I’ve had no issues for the 500 or so suppressed I’ve run through it.
If you're building something to shoot paper, steel or compete in PRS style matches go with the LMOS and H2 buffer.
If you're running suppressed I'd go with the FMOS or VMOS.
I've run a pair of JP's in 6.5 with every carrier weight suppressed and unsuppressed. They all run just fine without even tuning the gas from factory setting. There were minor differences in recoil but really it's splitting hairs. My favorite setup is still a SiCo Omega with the VMOS/H2 running 140 class bullets.
^^ Holy recoil......no thanks. There was a shotgun that used to cycle similarly. The whole barrel assembly cycled back toward the shooter. It died quickly because recoil was as to much. Think of all that mass coming back at you...yikes.
I got the BCG I linked in the quoted post. Looks great! Based off of internet pictures I'm aboout 99.9% certain that this BCG is made be the same company that makes Rubber City Armory's BCGs. I was also surprised to notice that the bolt has a
.068" firing pin hole so I'm going to use it with a 6.5 Creedmoor barrel.
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Is there any real need to headspace a rifle that is using a JP high pressure bolt & Proof carbon barrel? I'm hearing that the QC on those two parts is so high that I don't need to worry about checking headspace. (I don't have the gauges)
I bought the JP High Pressure Bolt but I did not purchase the carrier. Any issues with that? I kind of just planned on an Aero or Toolcraft carrier. The rifle is built around a 22" Proof Carbon barrel. Also, any need to headspace?
Ask Proof. I bet they're gonna advise that you check headspace, since they didn't have the bcg, when they cut the chamber. Is there a shop near you that could check it for you?
I've built up several Proof barrels with JP bolts in different calibers - .308, 6.5 CM, 6mm ARC, and 5.56.
Headspace has never once been an issue.
Headspace has never once been an issue.
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