300BLK - 187gr SPBT subsonic load recipe

[Bushwhacker]

https://youtube.com/playlist?list=PLTTrjvDib94kSvdzYsxkUab41PTxhtncm

This dude has compiled a ****ton of 300bo data.

several others on here have stated in the past that pills lighter than 190gr are hard to get subsonic out of a semi auto and still cycle correctly. but in for info if you find a good combo. I have a **** ton of 175/180gr pills.

yeah I've read 180 is borderline. But on other forums I've read people shooting suppressed getting sub speeds out of 165's reliably with certain powders. That's the thing u have cfe blk and N110 for these subsonic loads so I'm really trying to find a recipe for either of those specifically.

 

[Control for Smilers]

I am playing with h110 and imr4198. I will load up some 180 sierra's and try soonish.

 

[Dieseltech]

Ok I don't know what I was doing. I don't know why I said 187gr I have 180gr HPBT. Anyway so far I'm struggling to find a SUBSONIC load that will cycle consistently using CFE BLK. I have 1lb of Vihtavuori N110 in addition to the CFE BLK. Anyone have a good recipe for either CFE BLK or N110 and 180gr shooting sonic (for what it's worth I'm shooting suppressed)

What is it doing specifically when you say not cycling? Is it short stroking and not picking up the next round?
If so you could try a lighter buffer/ recoil spring and tune the gun to that specific load if that’s one you like and are wanting to keep running. Just a thought if you are happy with the results of that load other then it’s lack of cycling. Another option that is not as easy to reverse is opening up the gas port on the barrel and use an adjustable gas block. This will allow you to get as much gas as possible running your current load and then throttle it back for higher power loads.

 

[Dieseltech]

Jp rifles has adjustable buffer weight and spring kits so you can play with it and tune them in. Just don’t lighten it up for that load and forget to switch it back before shooting your full power loads again!

 

[Sneakypete]

Once again I have learn more about the 300 blackout just from this thread alone! Thanks ODT

 

[Ryan KM]

N110 is not a good choice for light subs, but N120 is. It’s slightly slower. Just FYI