I have seen several people post that they use 72.0 grains of RL-15 in the 375 with a 300 grain bullet but the Alliant manual and website list 66.5 grains as a maximum. I have worked up to 66 grains with no problems. Is the Alliant maximum load figure too conservative? Is the 72 grain figure I remember seeing a mistake? Thanks.

DrScott

RL-15 From 56.8 grains to 70.1 grains with Remington 9-1/2M primer

I am a very cautious shooter. I found 72.0 grains of RL-15 to give me my best load in a featherweight 375 H&H Pre-64 M-70 custom rifle as follows:

300 grain Barnes X
Winchester brass
F215 Match primer
72.0 grains Reloder 15
velocity: 2528 fps in 24" barrel
accuracy: 3/4 MOA for 3 shots

A classic load in my rifle. No problems.

In the past I have found RL 15 to vary quite a bit from lot to lot so this may be the reason for the apparently low powder charge listed. I have heard that Alaint is now providing RL 15 to the US Army in very large lots so maybe their quality control will improve.

My suggestion would be to work up a load you like and then buy more of it in the same lot.

Yep,
US Army spent millions studying this powder and others. RL-15 was the winner in accuracy, temperature stability, and overall, etc., etc., in the 308 sniper load. Quality control must have also been pretty good before the Army gave Alliant the contract.

This is the same U.S.A.F. that discarded the venerable .45 ACP in favour of the 9mm and awarded us with the 5.56/M16 and tossed the 7.62/M14!

There are too many factors I consider undesirable when it comes to milspec criteria over the last several decades.

I use Reloder powders and they definitely exhibit more variation than any other propellants in my inventory. They are accurate and meter well, but you might want to check out my post in the reloading forum regarding Nosler 85 grain ballistic tips.

Perhaps a big military contract will increase their quality control. We would all benefit from such a result.

Regards,

~Holmes

My experience with Reloader powders has been with 15, 19 and 22.

15 seems the best but I think that may also have someting to do with the fact that it has been loaded in calibers like 375 and 416 Rem, that is, small case capacity for the bore.

Certainly in 375s, Re 15 seems to offer the best combination of velocity, accuracy and non compressed loads of any powder.

If the American gov't is like the Australian gov't, then I would not regard the gov't selecting a powder as being a good endorsement

Mike

Agreed, Mike.

I have had excellent results with RE 15 & 19 in the 375 H&H. There have been variations but nothing I have not had with other propellants.

My best groups to date with the old H&H have been with RE 15 and Re 19 right behind it. In fact, I had 5 rounds of 71.0 gr Re 15 and 5 rounds of 73 gr RE 15 go into one ragged hole that measured 1.2". Like I say, 19 is only slightly behind it. That's pretty nice for an all around hunting rifle.

Using these powders in the 25-06 and the 270 has been rather interesting and really opened my eyes to the vagaries of cartridge design and characteristics.

I'll not be putting my Reloders away, just be watching them a little closer, especially in my varmint cartridges.

Take care,

~Holmes

Holmes,
I guess you mean U.S. Armed Forces, not U.S. Air Force, when you say U.S.A.F.

You must remember that the selection of the 9mm pistol and the 5.56 rifle were done with female troops in mind, no doubt. I abhor the choices too.

I think Army did good in the powder choice. Go Navy!

DrScott,
Don't forget to take into account the brass selection. Winchester brass is roomier inside than Remington brass in 375 H&H, 458 WM, etc.
Check the load sources to see which brass they specify. You have to use more of the RL-15 in the Winchester brass.

Norma 470 NE brass requires about 3 more grains of RL-15 compared to the BELL brass for similar reasons.