Home Forums Hunting & Shooting Express Rifles and Big Bores Only 375 Ackley Improved

Yes on the RL-17 Bob, my thought is its burn rate is very close to the 4350's, and in some cases gives a couple hundred feet extra velocity over the 4350's at like pressure levels, may be big fun

Gunner

mine gets a 270 gr. TSX over 79 gr RE15 for about 2750 fps from 21" barrel

I'll have to try RL-17 in my 375 Weatherby. It only has a 22" barrel but gets just over 2700 fps with 300g Nosler Partition factory ammo

Bob, at one time tinkered with a Ruger No. 1, an H&H blown out to the 375 Mashburn. I found eventually, it was just too heavy IMHO, to carry around between shots. But a 300-grainer at close to 2700 fps was pretty authoritative.

It was just another of a fistful of 375 "improved" that all do about the same thing. I liked the concept of power but need a lighter package, one of the motivations that finally resulted in shooting the 340 for years.

George yes, they all do pretty much the same thing..you do see an improvement in velocity no matter how you slice the pie....in truth I think it is pretty tough to tell an AI from a 375 Ruger today....at least from what I can tell.....that Thor rifle gave you light weight,but it rocked pretty good ,too.

I talked to Bill Steigers a few months back;he loved the 375AI,but said if he were doing it over today he would be reaching for the 375RUM,simply because it provided more capacity,and reached the velocities he wanted without having to lean too hard...

My .375 Ruger will run a consistant 2735 fps. with 300 gr.s. in a 9 1/2 lb. gun. That is fast enough for both me and the game.
I use a .375 Hawk at 8.5 lbs with 235's at 2700 for other stuff. The Hawk burns less powder and is more fun to shoot with less recoil.

I just use factory ammo. In my .375 Wby (DGR with 24" bbl), the Nosler factory 260gr AB load averages 2,974 fps chronographed out the muzzle. For apples/apples comparison, the published MV is 3,000 for that load (pretty close to what I get), and 2,750 fps for their factory .375 H&H 260gr AB load. That's about 250 fps faster. The Weatherby factory 300gr NP loads leave my rifle's muzzle at about 2,760 fps. That's about the same as most factory 260gr H&H loads, and about 60 fps faster than the typical factory 270gr H&H loads. Most factory 300gr loads have a MV of around 2,470 fps.

So, the way I see it, something like a .375 Wby will push a 300gr bullet about as fast as, or a little faster than, the H&H will push a 260gr/270gr bullet. I like that. I can't argue that it's necessarily better than an H&H in most situations, but I absolutely destroyed a 9'-2" brown bear with one of those 300gr Partitions at about 97-yds. The bear collapsed less than 25 feet from where he was shot. Though my experience is just annectotal, I wonder if that 300gr bullet moving at the appx 2,530 fps at that range might have worked a little better than the same bullet moving at a decent, but not as violent, 2,255 fps or so at the same range out of an H&H.

MH: There is no doubt that the various improved 375's(the Weatherby among them)move the entire range of 375 bullets faster than a 375H&H,which makes sense because they hold more powder,and I suspect in the case of the Weatherby,is also loaded to much higher pressures as well.....in the aggragate, this stuff adds up..

Do they show a material improvement in terminal performance? I dunno and I think you are already dealing with a pretty potent package with the standard H&H round,fully capable,so it's hard to say.....some would say "yes",but I suspect it has more to do with the bullets used than anything else.I would have to see a lot more animals shot with either one before I came to any firm conclusion myself.

Factory numbers are what they are...but I have seen a couple of brown bears killed with the 375H&H and 300 gr Partitions,and they went no where ...my last one (a 9'2")was killed at about 180 yards with a 250 gr Bitterroot started at 2940 from my 375H&H...(a load I have been using from the 375H&H for about 30 years now) he went no where at all,and exits were pretty impressive).

So, looking at that 260 AB load from the factory 375 Weatherby,it appears we are picking up about 60 fps,and 10 gr of bullet weight...no doubt the spread increases with the heaviest bullets,the larger case clearly having an advantage.

With the Improved versions of the 375, you get higher velocity, increased recoil levels;from a handloading perspective a shift to slower powders may be helpful in the larger case.Beneficial if we are to crunch numbers....I doubt the animals can tell the difference,

I got a couple lbs. of RL-17 and some 270 gn TSX'x, I need to go out to the shop this morning and see what they will run at in my old AI

Gunner

gunner, run it and let us know!

Load report coming up.......WOOOWWW! Bob you aint gonna believe this

Gunner

LMAO! You sound excited! tell us more!

Marine Hawk will be ecstatic!He might even take up handloading...

i'm runnin' RE 17 in my .375 RUM.

90 gr. RE 17 under a 260 NAB yields ~2990 fps at a calculated mild 60K psi from a 23" barrel. 90 gr. seemed like a nice round number

recoil is lively in an 8# rifle, but it shoots ~1 moa.

Bob, see new thread above

Gunner

toad that even sounds lively...

Gunner I will check it out.