300 Blackout

[Melnic]

What velocities are you guys running in supersonics?
I'm working with 150gr SMK and I"m getting 1800fps.
My accuracy was getting better as I bumped velocity so I plan to go further. No signs of pressure yet.

 

[DaemonAssassin]

I believe H-2. I was thinking of lightening it up.

Try the T-1 from Spike's. It is a standard 3.5 oz weight, just like the standard buffer with the disc weights, but has powder inside for weight and it is freaking quiet...

 

[DaemonAssassin]

What velocities are you guys running in supersonics?
I'm working with 150gr SMK and I"m getting 1800fps.
My accuracy was getting better as I bumped velocity so I plan to go further. No signs of pressure yet.

The lighter you go, the more velocity you get. I'm about to start trying a 125 TMK, using the standard 125gr load data from Sierra. I don't have my book in front of me at the moment, but it should be fast enough for what I want to do.

 

[Roadhawg]

The lighter you go, the more velocity you get. I'm about to start trying a 125 TMK, using the standard 125gr load data from Sierra. I don't have my book in front of me at the moment, but it should be fast enough for what I want to do.

I'm loading 125gr Nosler Ballistic tips with 17gr H110 which chronos at 2065fps.
Thinking about trying 110gr Nosler Ballistic tips and use 18gr of H110 for a 2285fps.

 

[Major03]

Also, get that .300 suppressed . It's what we built .300's for

 

[DaemonAssassin]

Also, get that .300 suppressed . It's what we built .300's for

No can for mine. I predominantly run supers out of mine for Bambi Slaying...

 

[clandestine]

Outrider58, I know nothing about reloading but I have seen lead projectiles foul up the AR Gas System. Check it with some weed eater to see if there is an obstruction.

Are you having cycling problems with non lead projectile subs or factory loads?

 

[outrider58]

Outrider58, I know nothing about reloading but I have seen lead projectiles foul up the AR Gas System. Check it with some weed eater to see if there is an obstruction.

Are you having cycling problems with non lead projectile subs or factory loads?

Will do and no.

These are poly-coated and are not supposed to have leading problems, but i will keep a close eye on it.

 

[Sticky]

Will do and no.

These are poly-coated and are not supposed to have leading problems, but i will keep a close eye on it.

I shoot poly (epoxy) coated and powder coated with no leading issues, and you should not get any leading gas from them, but... the wise one's advice should be heeded..

I start on the high side when loading subs for the 300, usually a bit over supersonic, test for proper cycling, then slowly bring the charge weights down until I am consistently below 1100fps (I use a chrono to verify when load testing). I will then reduce the charge even further to find the point where I am not consistently cycling, so I know how low I can go with that particular combination.

A1680 has proven very effective for me with subs in the 300 platform with both factory jacketed boolits and casts that I coat.

 

[Major03]

This is all part of the fun of reloading and building custom guns with uncommon calibers

DA's advice of looking at the buffer and spring assembly is spot on too. I'm using the same buffer.

 

[BenL]

Does anyone have a super load (125gr SMKs) that will reliably cycle a 10" gun? I've tried Lil' Gun (nope) and H110 (close, but still get a failure 1 or 2 times in a mag.) I picked up a Blastout for when I don't want to use a suppressor, but need a super load that will work.

 

[Speed3]

Does anyone have a super load (125gr SMKs) that will reliably cycle a 10" gun? I've tried Lil' Gun (nope) and H110 (close, but still get a failure 1 or 2 times in a mag.) I picked up a Blastout for when I don't want to use a suppressor, but need a super load that will work.

Hmmm I shoot the 125gr SST's with 17.4gr H110 with no issue? Probably shot 10 mags worth, not one issue.

 

[BenL]

Hmmm I shoot the 125gr SST's with 17.4gr H110 with no issue? Probably shot 10 mags worth, not one issue.

I loaded up 17.8gr, COL=2.06". Loaded up 90, shot through a Noveske 10" barrel (pistol gas system), had 4 failures across 3 mags; not enough gas to pitch the casing before grabbing the next round. The load worked fine in 16", and worked fine with the 10" with a suppressor.

 

[outrider58]

I shoot poly (epoxy) coated and powder coated with no leading issues, and you should not get any leading gas from them, but... the wise one's advice should be heeded..

I start on the high side when loading subs for the 300, usually a bit over supersonic, test for proper cycling, then slowly bring the charge weights down until I am consistently below 1100fps (I use a chrono to verify when load testing). I will then reduce the charge even further to find the point where I am not consistently cycling, so I know how low I can go with that particular combination.

A1680 has proven very effective for me with subs in the 300 platform with both factory jacketed boolits and casts that I coat.

Thanks sticky, I'll keep that advise in mind.

This is all part of the fun of reloading and building custom guns with uncommon calibers

DA's advice of looking at the buffer and spring assembly is spot on too. I'm using the same buffer.

I will be trying DA's buffer this Saturday. And yes, if you don't have failures, you don't learn.

 

[Speed3]

I loaded up 17.8gr, COL=2.06". Loaded up 90, shot through a Noveske 10" barrel (pistol gas system), had 4 failures across 3 mags; not enough gas to pitch the casing before grabbing the next round. The load worked fine in 16", and worked fine with the 10" with a suppressor.

Hmm I'm running the same barrel. Maybe buffer weight?

 

[DaemonAssassin]

I will be trying DA's buffer this Saturday. And yes, if you don't have failures, you don't learn.

 

[DaemonAssassin]

Hmm I'm running the same barrel. Maybe buffer weight?

I have found that a lot of issues on the 300BLK are due to the buffer or the gas system.

If you don't have enough gas to cycle the system, the lightest buffer won't help you. If you are over gassed, the heaviest buffer won't do much to totally resolve the problem of being over gassed.

I am running a Spike's T1 buffer (3.5 oz), because there are no sliding weights to make noise, while I'm deer hunting, just the powder moving back and forth. FWIW, the gas block is non-adjustable and pistol length gas. I really don't have problems with my rig.

 

[BenL]

I have found that a lot of issues on the 300BLK are due to the buffer or the gas system.

If you don't have enough gas to cycle the system, the lightest buffer won't help you. If you are over gassed, the heaviest buffer won't do much to totally resolve the problem of being over gassed.

I am running a Spike's T1 buffer (3.5 oz), because there are no sliding weights to make noise, while I'm deer hunting, just the powder moving back and forth. FWIW, the gas block is non-adjustable and pistol length gas. I really don't have problems with my rig.

I'll check this out. Right now, I'm using the buffer and spring that came with the Phase 5 pistol buffer tube. Maybe something lighter...

 

[outrider58]

Oh?

 

[DaemonAssassin]

Oh?

I'll explain Saturday.