I have been shooting my recently remodeled BRNO ZKK 375 with Hornady's 270 gr spitzer and it is shooting fine. Now I am going to work my hunting load using the subject bullet. I note that Barnes #4 shows 77 gr of Re-15 as maximum going 2800+ fps. Has anyone actually loaded 77 grs? Seems high and the velocity seems fast for a 270 gr.

Start with about 73 or 74 grains, going up one grain at a time, then shoot each load over a chronograph. When the chronograph reads 2800 or near to it, STOP. If you experience sticky bolt lift or flattened or cratered primers before you get to 2800 stop at least one grain short of the load that caused either of those side effects. For the cost of 5 bullets, primers and powder for each of the five you will KNOW. One rifle might dote on that 77gr load and another might lock up the bolt with a melted cartridge case stuck in the chamber. The only way to know for sure is to fire them in YOUR rifle.

BTW, I am doing this exact same excercise this morning to determine true maximum for my new to me 7mm Mashburn Magnum.

I've used 75 gr RL15 over the 270 gr TSX in three different .375s and it has worked like a champ in all three. As Mark suggests, I started with 74 gr and 75 worked so well I never went higher. Will be taking that same load back to Africa again next year.

Gents,

Yes this all I know. I was curious if anyone has made it all the way to the Barnes maximum or 2800 fps for that matter. Thanks for the replies.

Edited to add that after some "Google'ing" it is pretty clear that the Barnes max load and 2800 fps velocity is high and not safely possible for a number of folks that tried. I will work to 2700 fps and call it good.

FWIW, I am getting 2824fps in my Remington XCR II .375 HH using 78gr of RL15 and a 250gr TTSX. The book says I should get faster, but this is what I am getting.

When working up a load in my 375H&H Whitworth with the 270 TSX and RL15 this is what I got.
72gr-2634
74gr-2718
75gr-2757
76gr-2814
No signs of pressure.
Stayed with the 74 grs. as that load is a tac driver.

Mine went 2770 fps with 72.5 RL15, so start low and work up, it also was a Whitworth.

74grs and F210 primers for me. Got this load from our own JJHACK and it's super.

My buddy just gifted me a Whitworth 375H&H with great wood and a loopy on it. Saw this thread and have ordered up some 270 TSXs and RL15.

2,700 is not a bad performance by anyone's standards...more isn't necessarily better.....just more.

We reloaders can have a case of optalrectalesis at times.

Interesting. Why not F215 primers?

I use 73.5 gr RL-15 for ~2650 fps. I stopped there because it was for a plains game hunt, and it shot unbelievably well. Rifle is a Weatherby Mark V.

When I go back for something bigger, I'll work that load up a bit.

Have you looked at using IMR4831?

72.5 grains of H4895 worked best for the 270TSX in my rifle. 75 grains of Varget for the 270Horn. The best R15 did for any of my loads was @ 1.5".

The .375HH was designed around "Large Rifle" primers and was loaded with them until the "Magnum Rifle" primers came out, which were developed for the .300 Weatherby. I use the Magnum primers in my .375HH due to the colder temps that I hunt in (Alaska). I probably WOULDN'T use them in the hotter temps found in places like Africa or Montana.

A lot of people have reported gaining best accuracy when using the standard LR primers.

A good friend of mine who knows a few folks in the "business" with Federal, gave him that tip years ago. Basically, if you are shooting under 80gr of powder try using 210s instead. I've now tried this on four calibers and accuracy improved without any loss in velocity:
375 H&H
338 Winchester Mag
300 "

I did not have the same results with the 257 Weatherby however.

I use 76 Gr. of RL-15 behind a 270 Gr. TSX sparked by a Fed 215. Velocity runs 2744 fps and accuracy is great. Of course anyone trying this load should work up slowly and use a chrony. I stopped at this load since accuracy was great and I figured that this is fast enough.

i have had very consistant results with IMR3031
63gr= 2744fps
64 = 2726
65 = 2751
66 = 2789
67 = 2831 HOT

65gr is great providing 2750fps with f215 and 260NBT(discontinued) and 260NAB

all shots (64-67gr)were within 2.5" @ 100yds with a 1.5x5 vx3 leuy off a bench and bipod. the stud had to be reinforced for the bipod.

Well, after watching Brother Bill whack his rather large brown bear last year with the 270 TSX ahead of 75 grains, at 218 yards, I know it's enough.

I know that the 270 gr TSX and 75 gr of RL-15 will kill a 72" moose at 300 yds as well.

At least it did last week!

trapper, picture of the moose would be great!Congrats!

I watched last September as a pal worked up loads for a pre 64 M70 375H&H with 270 TSX and RL15(25" barrel).I recall he was hitting 2800 with the 270 gr but cannot recall the exact charge of RL15.