Hornady 208 ELD M, Vihtavuori N120 Subsonic

[Deude_Mann]

I have a curiosity question on the N120 powder. I am about to work up some subsonic loads using the Vihtavuori N110 powder in LC brass (cut down from 223). The bullets will be the 194 grain Lehigh expanding type. 16" barrel, 1:7 twist. It looks like Vihtavuori likes the N110 for super and sub 300BLK.

Any potential issues using the faster burning N110 over the N120? Any reason why you are using the N120 instead of the N110? I'm not trying to second guess anyone, just hoping I might learn something.

Thanks

I started developping a subsonic load for a 10.5 barrel suppressed and pistol gaz system with N110. As soon as my load went subsonic I started to get some cycling issues. I tried 190 grains HPBT to 230 grains casted bullets.

Now I switched to N120 and I get my bolt to hold open well below subsonic velocity. Night and day! That leaves plenty of room to work with the load. Only con : some unburnt powder residue that still needs to be investigated.

Same answer for both problems, change the burn rate of the powder.

For the 110 load you can try moving the bullet out some. This will slow down the burn rate giving you more gas when you need it, as the bullet leaves the barrel. To maintain velocity you might need to add powder, giving still more gas.

For the 120, do the opposite, move the bullet in. This will increase the burn rate and pressure at it's peak and will burn cleaner. You will also need less powder to get the same velocity, further reducing what's left behind.

Useeful information Yugnat and dellet, thanks.

[mauidiver]

So ran my first few subsonic rounds today. This was my first go at reloading. Only shot a few, but here are the numbers.

208 grain Hornady ELD M
2.250 COL

Only had 2 rounds of 11.5 -(1st) 1207, (2nd) 1204

Then went down to 11.0- which ran at 1182
And one with 10.3- 1031

PWS MK111 Mod2 piston

N120

What is your final case size? I had quite a few rounds that I stuck in Hornadys case gauge and was not flush, so didn’t run those. Thanks for your guys help.