300blk sanity check

[ny32182]

I have the following:

150gr Hornady FMJ
H110

After reading around on 300blktalk, it seems 2.065" was recommended, and that looks like it stacks well in a PMAG (bullet just barely off the rib in the magazine... looks to me like they will feed well without binding).

There seems to be a lot of variance in powder charges that people are using.

I'm planning on starting at 15.7gr of H110.

Seems like you want to work up to a velocity of 1900ish FPS, eventually. Barrel is a 12.5" AAC.

Does this sound reasonable? I'm just trying to avoid repeating my 300blk experience from a year ago (kb on the 18th round ever through the gun, shooting factory reloads. Ammo company paid for everything; I can't discuss any further detail due to a contract I signed with them when they reimbursed all my expenses)

 

[SCC]

My cheep supersonic plinking round is 15.5gr H110, 147gr M80 bullet seated to 2.14" (middle of the cannelure), no crimp and CCI #450 primers. Velocity 1685, ES 42, SD 12, 10 shot test. Barrel is 8" 1:7.

It's not a particularly accurate round, but good enough for 50-70 yards. You're in the right ball park.

---Scott.

 

[ny32182]

Thanks... what do you think we would consider a max velocity for this bullet in 300blk with this powder?

 

[yugorpk]

My normal plinking round is a 150 Hornady soft point with 16.5 grains of H110 at 2.20" . Feeds in all the mags I have at 1950 FPS out of a 10.2" barrel

 

[ny32182]

Perfect... thanks!

 

[dh1633pm]

Mine is the exact same as Yugorpk. The same load that has perpetrated everywhere on the internet as a good load. Please note that 16.5 is a couple tenth's over the Max for H110 per the power manufacturer's published data. Its shoots nicely out my Remington 7 AAC Blackout with a 16 inch barrel. I have not clocked the round. It is accurate.

 

[SCC]

I stayed conservative on the velocity. It's not a hunting round, just for paper punching and ringing some steel. Looked at Hodgdon's data and picked 15.5gr because it was near the middle of the range for a 150gr bullet. It worked good enough and showed no pressure signs, so I never tried to optimize it.

 

[yugorpk]

I have heard of people going up to 17.2 grains H110 with a 150 but I don't do it or see the point.

FWIW 9.7 grains of H110 with a 225 Hornady bullet makes a great subsonic round in SBR's that still cycles the bolt 100% . Its a very versatile powder. Helps that the cartridge is filled mostly with bullet.

 

[SCC]

Interesting. My 225 Hornady load is 9.0gr for 1010fps. About the same velocity out of 8" or 16" barrel, though the SBR really prefers 10.5gr AA1680. Don't have to open the gas port as much with the 1680. COL 2.22" and CCI 450's for both.

 

[yugorpk]

I cant cycle fully with 9.0 grains in my 7.5" AR. 9.5-9.7 grains and I can cycle just fine and keep the speed at 1050 +/- 20 fps or so. Ive even run up to 1120 before the sound becomes noticeable through the SpecWar. Ive got quite a stash of 1680 ( 8 lbs ) but I try to be conservative with it by trying other powders to do the same thing. 4198, 4227 and H110 are my staples as I can get them locally easily RIGHT NOW. As far as primers go I get equal results with small pistol and small rifle primers for subs.

 

[SCC]

I might be getting a little boost from the magnum primers.

BTW my favorite sub load is a 175gr M118 (similar to the SMK) with 11.8gr AA1680, COL 2.075". The COL on this one is touchy. A little shorter and accuracy drops off. Longer and the ES goes up. YMWV.

 

[rg1]

I load 147 gr. M80 and 150 Hornady 150 FMJ's at 16.5 grains of H110 using RP 7 1/2 primers in LC formed brass. No issues. I get approx. 1950 fps in a 16" barreled AR. Both 147 and 150 gr. get seated to the cannelure at 2.130-2.140" for the 147 fmj and Hornady 150 fmj's at approx. 2.065". Just make sure the necks of your loaded rounds are .334 or less in diameter. Some brands can have too thick neck walls.

 

[oldpapps]

Sounds like a good place to start.
Every weapon is different so keep a close eye on pressures.

This is what I get with my 16 inch barrel. Brass is mixed GI recycled. This is for information only and may not be safe in all weapons with all components.

M2 GI 147 H110 16.4 1928 DSA 5/8/2012 2.065in
M2 GI 147 H110 16.6 1945 DSA 5/8/2012 2.065in
M2 GI 147 H110 16.8 1948 DSA 5/8/2012 2.065in
M2 GI 147 H110 17.0 1988 DSA 5/8/2012 2.065in
M2 GI 147 H110 17.5 1993 DSA 9/22/2012 2.065in


The 16.6 grain charge gave the best accuracy. For my spreadsheet to display, a minimum of 15 samples are needed. I use old metal GI mags and have no problem feeding.

Hope this helps, take care.

 

[Reefinmike]

I load the same bullet to 2.100" with 16.5gr w296(same as h110). Depending on your data source, this is right at if not above max charge so work up accordingly. These function 100% out of my 10.5" ar barrel. They average 1933fps with a sd of 14. Charged with lee pro autodisk.

 

[dh1633pm]

With a bolt gun I am able to load mine out a little longer. No mags to cause me issues. I think the 16.5 became the defacto load with the 150 grain during early development when no loading data existed.

 

[yugorpk]

The 16.5 grain load is a good load so its stuck around and become very popular.

 

[ny32182]

I'm up to 16.45gr H110. I chronoed at 1884 fps average yesterday with the temp at about 37 degrees F.... I am wondering if this powder is a little temp sensitive and that is the reason I'm not getting quite the velocity others are listing. Or maybe barrel length matters.. this is a 12.5".

Just trying to decide whether to take this one up a little further or not.

 

[Reefinmike]

I'm up to 16.45gr H110. I chronoed at 1884 fps average yesterday with the temp at about 37 degrees F.... I am wondering if this powder is a little temp sensitive and that is the reason I'm not getting quite the velocity others are listing. Or maybe barrel length matters.. this is a 12.5".

Just trying to decide whether to take this one up a little further or not.

I wouldnt go any further especially an an autoloader. I start seeing some ejector damage on the case head at 16.7. Next time at the range Im going to try out some lilgun. In 357 mag rifle, it gives me a 200fps increase over max w296 charges.

 

[ny32182]

That is kind of unfortunate since I already loaded up some 16.8gr loads. I guess I will chrono the 16.5's in warmer weather and then if they are running 1950 I'll tear down the hotter ones.

I'm assuming 1950 is the goal here at this point.

 

[ny32182]

Today I got back to the range in much nicer weather (65 degrees F). I re-chronoed the 16.5gr loads, and they only went up 8fps on average to 1892fps, average of 6 rounds. So I have to conclude that this powder is not very temp sensitive.

I decided to shoot the 16.8gr loads as well. Primers did not appear flat or anything; I could not see anything that looked like an over expanded case head, but the one difference is that rather than just a slight drag mark on the brass, the ejector was actually shaving paper thin flakes of brass which were visible on the bolt face. Average velocity was 1925fps. It is hard to tell, but I think the action was running a little bit faster.

I don't think there was anything unsafe going on with the 16.8gr load, but given that the 16.5 runs the gun nice and smooth and I'm only punching paper, I guess I will stop there even if I'm not getting quite the same velocity as others with this bullet. Should get several loads out of the brass and be a little less over-gassed with the can on it.

 

[popper]

16.8 of H110 pushes H 150 SP to 2000 fps in my 18" 1:10 BO. 1 1/2 MOA. Not a target bullet.