Gas checks for .300 BLK subs?

[nso123]

I hope my first post is not a question that has been hashed over time and again, but I did not find an answer in the search function.
Do you need to use a gas check for a subsonic load in .300 Blackout? I am thinking that the answer would be no, but I didn't know if it might affect the gas system by not using the gas checks. Please share your advice with me if you will.

[Smoke4320]

If you are powdercoating the base I can tell you no check needed at all to over 1900 fps
If plain lubed bullets I have no experience

[nso123]

Thanks for the reply. In order to keep the load subsonic, it will have to stay below 1100 fps roughly, which is what leads me to believe that I would be safe without the gas check or powdercoating. I just don't want my assumptions to make an *** out of me.

[Motor]

If you are powdercoating the base I can tell you no check needed at all to over 1900 fps
If plain lubed bullets I have no experience

Great !! I was just about to do some testing with the 300 BO. I'm still using gas checks on my "high teens" velocity loads (other calibers) but was thinking about trying them without. I don't use them on some pretty warm 500 S&W loads and they work great.

It's just hard to change something that works really well.

I have never used a gas check on a sub-sonic load, not lubed or powder coated.

The thing that worries me about the 300 BO is the pressure. It takes a lot more pressure to get 1900 from the BO than it does from a .308 or 7.5MAS or 54R.

Motor

[Smoke4320]

To clarify a little more (I hate typing on a cell phone) I am getting great accuracy with all my loads up to about 1650 using 50/50 mix with 2 % tin and powdercoated ..over 2000 FPS with 98/2 powdercoated No gas check on gas check molds .. After 1900-2000 FPS I am finding my accuracy improves with a gas check ..
I have recovered bullets fired at over 2000 up to 2500 FPS with just powercoated bases and the coat is still there but not good accuracy

I shoot mostly suppressed rds now so I don't want the possibility of a gas check getting in the suppressor and causing issues

[nso123]

To clarify a little more (I hate typing on a cell phone) I am getting great accuracy with all my loads up to about 1650 using 50/50 mix with 2 % tin and powdercoated ..over 2000 FPS with 98/2 powdercoated No gas check on gas check molds .. After 1900-2000 FPS I am finding my accuracy improves with a gas check ..
I have recovered bullets fired at over 2000 up to 2500 FPS with just powercoated bases and the coat is still there but not good accuracy

I shoot mostly suppressed rds now so I don't want the possibility of a gas check getting in the suppressor and causing issues

I had not even thought of a gas check getting loose in the suppressor. Thanks for mentioning that. That would be a good way to get a baffle strike, I suppose.

[Ola]

I had not even thought of a gas check getting loose in the suppressor. Thanks for mentioning that. That would be a good way to get a baffle strike, I suppose.

Absolutely. NO cas check with suppressor!

[nso123]

Thanks for the replies. I will proceed without the checks.

[brstevns]

What weight bullet and powder are you using? Care to share a few loads?

[Smoke4320]

Brstevns if you are talking to me about 300 blkout loads I can post some tomorrow. Out of town right now....

[brstevns]

Brstevns if you are talking to me about 300 blkout loads I can post some tomorrow. Out of town right now....
Yes Sir. That would be great!

[Smoke4320]

172947172947172941172942172943172944172945172946 I also have a load for the Mil hec 311-159 HP that I just love .. did not have a Pic saved try to post that tomorrow

[brstevns]

Thanks for posting.

[Smoke4320]

First 2 pics are from a Ruger American

[Smoke4320]

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[Smoke4320]

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[Smoke4320]

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