Possible new 300BLK Bullet to try..

[jcj]

I just got an email from Missouri Bullet Company about their "new" coated bullets.  I hadn't looked at their offerings in a while so I checked it out.  Looks like they have some 245GN RNFP coated bullets that might be good for 300BLK sub rounds. Pretty sure they've had something similar in an un-coated variety for a while now, but I haven't used those either.

 

Anyone gave them a shot?

 

http://www.missouribullet.com/details.php?prodId=204&category=20&secondary=&keywords=

 

[Hozzie]

I have a 1000 non coated sitting here and just haven't got around to doing much with them.  I loaded 20 test rounds and have only shot 5 of those before I realized I didn't have the shoulders bumped down enough.  I fixed that and still need to get back out and do some testing.  I did powdercoat some of mine though since I will be putting them through a suppressor after I make sure they aren't tumbling.

Edited October 22, 2014 by Hozzie

[dcloudy777]

That's pretty cool... but what I'm really excited about....

 

http://www.ar15.com/forums/t_1_5/1674562_OMG_success_30_cal_subsonic_expander_.html

[jcj]

I have a 1000 non coated sitting here and just haven't got around to doing much with them. I loaded 20 test rounds and have only shot 5 of those before I realized I didn't have the shoulders bumped down enough. I fixed that and still need to get back out and do some testing. I did powdercoat some of mine though since I will be putting them through a suppressor after I make sure they aren't tumbling.

Out of curiosity, what powder are you using with these?

[Dolomite_supafly]

It depends on what length gas system and whether you are using a suppressor what type of powder you need. Pistol length gas systems, regardless of barrel length, work with a wider variety of powders while a carbine length gas system is very, very limited. I will say that subsonic load out of a carbine length gas system will be problematic.

 

If you could give me the specs on your gun I can recommend a powder that will probably work.

[Hozzie]

Out of curiosity, what powder are you using with these?

 

Right now, IMR4227, but I will also start some with 1680.  I am shooting them in an 8.5" barrel with Pistol gas system.

Edited October 23, 2014 by Hozzie

[Dolomite_supafly]

A1680 was miserable for me. I got ES of 100+ fps. Lil'Gun works a whole lot better with pistol gas. With Lil'Gun I was getting single digit ES numbers.

I have recently started using IMR4227 and really like it so far.

[Major Kong]

A1680 was miserable for me. I got ES of 100+ fps. Lil'Gun works a whole lot better with pistol gas. With Lil'Gun I was getting single digit ES numbers.
I have recently started using IMR4227 and really like it so far.

It's easier to find unicorns than Lil Gun right now. I've enjoyed 4227 with the Missouri Bullet coated bullets.

[2006Blackpearl931]

What a deal. I will be ordering some today!

[jcj]

It depends on what length gas system and whether you are using a suppressor what type of powder you need. Pistol length gas systems, regardless of barrel length, work with a wider variety of powders while a carbine length gas system is very, very limited. I will say that subsonic load out of a carbine length gas system will be problematic.

If you could give me the specs on your gun I can recommend a powder that will probably work.

Thanks Gordon! 10.5", pistol gas system. Adjustable gas block. Shooting suppressed with a YHM Phantom LT.

[Dolomite_supafly]

10.5 grains of IMR4227 works really well in my 8.5" gun so that is where I would start with IMR4227.

 

BTW, I have found that cast bullets, even coated, that are over 230 grains use data that is very close to the same date as 220 SMKs. I know my 247 grain loads using cast bullets use the exact same data as 220 SMK's.

 

The fear isn't too much powder with subsonic loads but too little. I would take whatever data you find and add a grain as long as it is an appropriate powder for 300 Blackout. Doing this will ensure the bullet is both fast enough to leave the barrel as well as be stable when it does. Just because a load cycles does not mean the bullet is stable, velocity is what ensures the bullet is stable.

 

This goes without saying but ALWAYS shoot your loads WITHOUT your suppressor until you feel comfortable they are stable. I test mine at 10-25 yards and if the bullet holes are nice and round they are probably going to be stable enough to make it out of the suppressor.

[jcj]

10.5 grains of IMR4227 works really well in my 8.5" gun so that is where I would start with IMR4227.

BTW, I have found that cast bullets, even coated, that are over 230 grains use data that is very close to the same date as 220 SMKs. I know my 247 grain loads using cast bullets use the exact same data as 220 SMK's.

The fear isn't too much powder with subsonic loads but too little. I would take whatever data you find and add a grain as long as it is an appropriate powder for 300 Blackout. Doing this will ensure the bullet is both fast enough to leave the barrel as well as be stable when it does. Just because a load cycles does not mean the bullet is stable, velocity is what ensures the bullet is stable.

This goes without saying but ALWAYS shoot your loads WITHOUT your suppressor until you feel comfortable they are stable. I test mine at 10-25 yards and if the bullet holes are nice and round they are probably going to be stable enough to make it out of the suppressor.

Thanks! I've got an order of those Missouri bullets in the original post on the way and I just happened to have some 4227 on hand. I'll work up a few and see how it goes.