I was at the range today testing out a new longer length A5/AR10 buffer tube I installed; swapping various buffers to try and tune it well. I recently rebuilt the whole upper and now the new receiver extension. About 10 rounds into the range session my bolt catch was snapped in half. I'd guess the lower has about 750 rounds through it with that bolt catch. I wouldn't even have noticed except I went to drop the bolt on a new mag and half the button was missing, LOL. I pulled the broken pieces out and burned through another 100 or so rounds flawlessly - just without last round bolt hold open.

For what it's worth, a 14.25" barrel with a .073" midlength port and Slash 8.5oz XH buffer (no adjustable gas) cycles perfectly; 10ft ejection @ 4:30 o'clock unsuppressed and about 12ft @ 3:00 o'clock suppressed. I think I need to drop a quarter or two in the buffer tube though to limit bolt over-travel if it's going to make a habit of breaking bolt catches... or at least buy better bolt catches.

Can anyone recommend me a top quality bolt catch that fits the Black Rain 308AR receivers (DPMS pattern).

V Seven

1. Aero Precision makes a good replacement that does fit your LR308

2. This is a good excuse to pick up spares for this just in case there's a next time.

3. Sorry man, that sucks.

Funny thing is, I measured the bolt over travel past the bolt stop after installing the new tube @ ~5/16" so I dropped one quarter down the tube. I guess I need to drop 2 or 3 quarters down the tube though.

Plus, my new Slash XH buffer in the A5 RE has a much bigger bumper pad than my old Slash Car-10 buffer in the carbine RE so I'll bet he new buffer pad compresses MUCH more.

Bolt catch breakage on the AR10 is pretty common when you shoot higher volume, and especially shooting suppressed.

Cyclic rate plus the massive BCG of the AR10s increases the force imparted to the bolt catch, and something has to give on a non-tested part.

Even on the M4 TDP Mil-Std, the small parts have to be tested and made from certain alloys, under very specific conditions, processes, and then analyzed to ensure correct structure of the parts.

The are surface hardness and ductility requirements based on how the part is meant to work in the system.

I've just watched it happen in real-time over the years.

1st AR10 bolt catch I saw break was on an ArmaLite AR10T shooting suppressed overseas with a coalition military partner nation.

I also seem to recall some scuttlebutt about it in one of the shoot-offs for the Army's SASS competition, where one of the entrants had that happen during the course of the shooting tests.

Over the years here on the forum, there have been many people with the same thing happen to their AR10s, DPMS LR-308s, and the new wave of AR10-inspired rifles with bare bones cheap parts used to race to the bottom of price points in order to make margins on sales to customers who never would know the difference until one snaps off at the range or in a shooting course.

The question then comes back to, "Who makes reliable ones, and what are you willing to pay in order to not have this happen to you?"

So I like the look of that V Seven unit, and it's tool steel. But that Aero part looks much beefier around the pin hole, and that's right where the last one broke. Not sure which to get...

No, it broke so I tossed it in the range trash can and kept shooting.

Receivers are Black Rain matched billet set and the original catch was a DPMS LR308 I put in it 4 years ago when I assembled it.

I'm just going to buy both the tool steel V Seven (lifetime warranty) and the beefier Aero A5, if they both fit, good... I've got a spare.

Both!

And get more roll pins for them too.

And I think that V7 was started by a former employee of John Noveske who left the company after he died.

Forward Controls design seems like a stout piece. Haven't tried it yet, but seems solid in hand. Has a decent heft to it.

The dpms and others feel like cast crap. Way too light.

That is hard on the bolt catch!

Meh, a standard Armalite AR10 carbine and rifle buffer is like 5-1/2 oz and they're generally quite overgassed, too ... so a 8.5oz buffer isn't all that crazy. I mean, that's why AR10/LR308 catches are beefier, right?

I'm going to play with some spacers in the tube and reduce the bolt overtavel past the new bolt catch. If it still makes a habit of breaking catches I can always dial the gas back some and try for a standard H3 buffer weight and/or lightened carrier.  But my understanding has always been the heaviest buffer that gives proper ejection without over-gassing should also provide the best reliability, no? To me it makes sense more momentum would power through dirt and fouling more easily and also provide a more stable bolt velocity versus cool to hot loaded rounds. When you start making bolts, buffers, and recoil springs too light in any AR, it can get finicky about fouling and under/over powered ammo.

Id go with the KAC, Ive always liked the looks of it with its larger paddle.  BUT.... just looked at the vseven, s7 steel for $30, thats tough to beat.

When you manually pull the BCG all the way back the bolt should only be 1/10 to 1/8" behind the bolt catch. If you were at 5/16" you'll probably need 2 or 3 quarters.

Would this be a good application for "tool steel"?  I have the impression that "tool steel" was was hard but brittle.  Has better wear characteristics but being hammered by the bolt , ....seems it may not be the best choice of material.

S7 steel claim to fame is that it is the steel used in jack hammer chisels.  It is a tool steel that is very impact resistant.  (s7 info)

There actually are some Technical Packages for 7.62 NATO chambered SR25s, AR10s, M110s, and others within the US military.

The US materials/alloy, MPI testing, strength, and dimensions of the bolt stop are included in that package.

Not an exspurt , but switched to adj gas block after beating/breaking parts with heavier buffers/springs.  Could get good timing without the adj gas, but the particular rifle wasn't designed for longevity with the heavier buffers/springs.  Especially suppressed.