I couldn't find published data for 300MP at Hodgdons site. I would like to know where you found published data as I recently acquired several pounds of 300MP
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I couldn't find published data for 300MP at Hodgdons site. I would like to know where you found published data as I recently acquired several pounds of 300MP
Sorry I meant it as a caution to use published data not mine. I never meant/said that the Hodgdon site had data for 300MP however they do have data for 296/H110 which is close to 300MP on the burn rate chart.
Was out testing last week with a 9.5" Core15 suppressed SBR.
Load data:
125 Speer TNT
New converted LC brass, 1.360 case length
CCI #41 primers
OAL - 2.120"
Did a ladder with 16.5, 17.0, 17.5, 18.0, 18.5, and 19.0 gr of 300-MP. Accuracy was good with all loads, but best with 17.5 gr with a 2" 5-shot group (using an Eotech at 100 yds). No serious pressure signs were seen but 19.0 gr loads started to show a tiny bit of primer flattening. Temp was 60F. No chrono data unfortunately, but 300-MP seems to have a very linear pressure curve and is cleaner than H110 for sure.
Did some more load work on the 147fmj. Shot out of a 16" 1/8 twist.
147fmj surplus (wt checked to exclude any heavy ones)
Mixed converted brass
Tula K223 primers
OAL was 2.150
17.5gns 300-MP
"Beta" chronograph
Avg. 1999 fps. Chrono was set up 14' from muzzle.
Temp 62 degrees.
The JBM ballistics computer shows this to be a deadon hold out to 175 yards as its trajectory will be only 1.3" high at 75 yards and 3.9" low at the 175 yard mark.
Think this is going to be my "pet" load for the 147, went up to 18 grains and only saw very small gains in fps. Heck, don't see a need to push these pills any harder. NO signs of high pressure when fired in MY rifle and very accurate. Your results could vary and it is suggested you start with a reduced load and work your way up.
Read my post about 3 above yours.......although I have not ventured in the 150gn much, the 147gn give every indication you can use 150's with this powder. I have shot 150 corelokts at 16.5 and 17.0 without pressure signs. The 17.0 was more accurate. I was just focusing more on the 147gn. right now. I have shot a few 150 GMX's at 16.0, while accurate they did not cycle the action......so it will take more loads and time to get them to where I want to be. A work in progress that I am enjoying right now!!
I don't think I am going to look at loading heavier then 150gn (as I have a bunch of those) but instead look to going to lower weight to increase velocity. The Barnes/GMX type bullets allow you to use a lighter weight projectile while achieving great penetration, and expansion. I have yet to recover a Barnes TSX from either deer or elk when shot with a .30 caliber projectile!! I think I will find my hunting loads in that bullet type around 110-130 grain....only time/testing will tell!!
Loading caveat:
All of my loads are safe in MY rifle with a 16"barrel and 1/8 twist. That does not mean they are safe in yours, work your loads up from well below my loads and watch for pressure signs.
attila. wrote:Did you see any pressure signs with that high a charge?
No, everything looked good. I'd earlier worked up to that same charge under a Nosler 125 BT, and that showed very slight primer flattening. These bullets sit longer, and leave more case capacity.
I'm hoping I found that sweet spot just under max, will load some more to test.