Just a side note on running heavier pills at slower speeds for down range power, basic specs for the ARX
125g @ 2635fps MV energy 1927 ft-lb @ 400 yards 827 ft-lb
155g @ 2435fps MV energy 2041 ft-lb @ 400 yards 1068 ft-lb
Mighten seem much but shows that a bigger, heavier & better BC bullet holds far more energy, you do need a bullet that will work & expand at lower speeds though.
Shoot it, root it & then BBQ it !!!
I had a look through the simple bullet drop app. Up to about 400yrds a 120BT at 2900 vs 140BT at 2700 and 162ELD at 2450 are pretty close. The 162 has more retained energy and less wind drift but the 120 less drop by about 6inches
Given energy is only good if imparted on the animal (and I do like an exit) I’m now leaning toward at 140BT as being best compromise for the short 7mm08......the debate continues. The drop at 400yrds is about the top of the post on the little 4.75x40 Weaver Grand Slam and that’s more than far enough for this combo.
Anyway I’ll try the 139SSTs Factory’s first and if they are accurate I might not be hand loading the 7mm08 in any case.....
Yeah I have done a lot of math and comparisons as well for me drop doesn't come into it as I have a good scope that I can dial or hold over with, and energy on target is only part of the performance on game which I will explain next.
A few of years ago I was looking around on the internet for heavy 7mm08 load's as I wasn't really getting good performance with the 139/140 gr bullets I had been using. While on this search I came across a statement that the heavy bullets in the Sierra 7mm range where only suitable in the magnums as they where too "hard" to be used at standard velocity's. Not taking anybody's word for it I email Sierra and asked the question, the reply I got was "You need at least 2000 FPS on impact for reliable expansion with all 3 of those bullets". This was for the 150, 160, 175 Gamekings. So I ran some numbers through a ballistics calc and the original statement holds true with Sierra bullets, you just don't get enough of an increase in BC to overcome the velocity drop to warrant going to a heavy bullet in the Sierra line. Actually for a laugh I ran the 120 Prohunter and it came out on top at 350m (380Yd) but the wind drift was pretty bad.
Admittedly since then there has been a big advancement in bullet technology and this may longer ring true, But since then I have used 2000fps as a minimum velocity rather than the often quoted 1000 ft/lbs of energy when deciding on how far I could theoretically shoot with a given bullet.
I reckon the 150 ELD-X would be one of the better choices from bush distances to as far as you could comfortably shoot, if you can get them to group in your rifle.
Just some food for thought.
BC doesn't matter, until you need to dial
Given a few people suggesting 760 powder has anyone worked up some loads with STABall powder? Less temp sensitive based on the marketing information. I’m sticking with 120/140 BTs as the short barrel ideal as I don’t have a dial up scope and have a 284 for longer range if needed
This is a wheel that probably doesn't need re-inventing. Just run with the classic 2208/ 120 TTSX combo which is easily good for 2900, or if velocity's your thing, use CFE223. Those TTSXs kill well and have massive penetration, in fact most go right through, so there's no need to consider heavier projectiles IMHO. Fine out to 350yds.
I cant comment on performance of factory ammo in short barrels, but im picking velocity will be quite slow.
I use to run 120 nbt with cfe223 for just shy of 2900 fps from my 15 inch barrel M7.
Worked well, but changed up to the 140NBT at 2700 with same powder for a bit more distance and they shot slightly better in my barrel
Win760 gives 3050 with the 120ttsx in 18 inches
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