338 RUM load success with 285gr BTHP

[aramarine6]

So after 2 years of building a rifle and developing a load I have finally achieved success. Since 300 smks have been next to impossible to find in the past 6 months I had to develope a load using Hornady 285 gr BTHP. After much research I had turned up next to nothing on loads for the 388 RUM using this particular projectile. I did what most reloaders would do and found a smiliar weighted bullets load data and started with the absolute minimum powder charge and worked up. I used H1000 because it was readily available at my local cabelas. I started somewhere around 87 grains and ended up going up to 97 grains in half grain increments. 97 was way too hot and 96.5 was having some extraction issues. Here is the final load I have settled on:

Remington 700 with a 26" GAP barrel 1/10 twist 5R rifling.
338 RUM
96 grains H1000
Remington Brass
CCI magnum primers
285 grain Hornady BTHP
COAL 3.72

Velocity 2960
SD 7
ES 14

Keep in mind that I was able to load this round much longer than all the books tell you. Therefore increasing powder capacity and decreasing pressure. DO NOT attempt this load at the saami COAL spec of 3.6 for obvious reasons.

I'd like to thank my buddy Mike for helping me with this very long process.

Now I just need a muzzle brake!

 

[highridge1]

That is a stiff load for the 338 rum. MY 2 338 edges would not go to 96 grs. 95 was right at max with the 300 gr SMK and never got over 2900 fps for velocity with a 28 and 30 inc barrel. bullet seated at 3.9 Those are some impressive numbers for the 338 RUM with a 285 gr bullet and only a 26 inch barrel .Are you getting a ejector button stamp and flat primers?

 

[aramarine6]

That is a stiff load for the 338 rum. MY 2 338 edges would not go to 96 grs. 95 was right at max with the 300 gr SMK and never got over 2900 fps for velocity with a 28 and 30 inc barrel. bullet seated at 3.9 Those are some impressive numbers for the 338 RUM with a 285 gr bullet and only a 26 inch barrel .Are you getting a ejector button stamp and flat primers?

It's stiff alright. So Is my shoulder. At 97 grains I needed a mallot to pull the bolt back. WAY to hot. As for 96 grains I've got ZERO pressure signs. Being alittle skeptical myself and thinking the chrono was reading gas blow by speeds, I pushed the chrono out to 15 yards. And it was still giving me great readings. My buddies 308 was dead nuts on. And we both confirmed our drops using a ballistics calc and shooting out to 400 yards. Idk if I've got a fluke of a barrel from GAP but the velocity is good to go. Still looking for a brake to save my shoulder tho.

 

[D.Camilleri]

This does seem to be a pretty hot load. I load 97 grs of H-1000 with a 225gr accubond for 3300 fps and 90 gr of H-1000 with the 300 gr Berger for a drop chart verified 2830. I have an older lot of H-1000 that is nowhere near as hot as the newer lots and I don't use it. Be careful when you change powder lots so you don't get a bad surprise. How are your primer pockets when reloading your brass? If your pressure is over the top, your primer pockets will open up in a hurry.

 

[varmintH8R]

I started somewhere around 87 grains and ended up going up to 97 grains in half grain increments


Now I just need a muzzle brake!

I hope that rifle weighs about 60lbs! Bet you took a beating doing that much load development without a brake!

As others have stated, be cautious with that load. There is no free lunch - at a given barrel length velocity has to be derived from pressure, whether it is obvious in looking at your brass or not.

 

[338RUML]

So after 2 years of building a rifle and developing a load I have finally achieved success. Since 300 smks have been next to impossible to find in the past 6 months I had to develope a load using Hornady 285 gr BTHP. After much research I had turned up next to nothing on loads for the 388 RUM using this particular projectile. I did what most reloaders would do and found a smiliar weighted bullets load data and started with the absolute minimum powder charge and worked up. I used H1000 because it was readily available at my local cabelas. I started somewhere around 87 grains and ended up going up to 97 grains in half grain increments. 97 was way too hot and 96.5 was having some extraction issues. Here is the final load I have settled on:

Remington 700 with a 26" GAP barrel 1/10 twist 5R rifling.
338 RUM
96 grains H1000
Remington Brass
CCI magnum primers
285 grain Hornady BTHP
COAL 3.72

Velocity 2960
SD 7
ES 14

Keep in mind that I was able to load this round much longer than all the books tell you. Therefore increasing powder capacity and decreasing pressure. DO NOT attempt this load at the saami COAL spec of 3.6 for obvious reasons.

I'd like to thank my buddy Mike for helping me with this very long process.

Now I just need a muzzle brake!

I doubt i will get a reply two years later but hey! What was he C.O.A.L I'm guessing you had to shoot it as a single shot?

 

[aramarine6]

3.72 coal. And since this post I've backed the load down to 93 grains of H1000. 96 was too hot of a load during the summer. I'd get a stuck bolt every couple shots. 93 grains im still getting 2775 fps and is still a half moa out to 1000 yards. I'm going to have to build a new load because Remington brass is non existent right now and I'll be switching to nosler brass.

 

[Woodo]

Do you have any current load info on your 338 RUM with 285 ELD-X? I'm testing on 28" 1-9 Lilja barrel.

 

[aramarine6]

I have some loaded up for testing but I've been saving up for a new scope to really ring the accuracy out of it. I can tell you that since my original post I've dropped the load down to 93 grains of H1000 which extends my brass life and I don't have to worry about pressure problems in the summer heat.

 

[Woodo]

I did some testing yesterday and shot some great groups with 86.0 H1000 on the ELD-X 285 at 2780 fps. 86.5 opened up some so I might go up in powder charge and see if it comes back together. I shot some great groups with Accubond LR 300 with IMR 7828ssc at 86.0 2 groups at .41, pushing 2856 fps, couldn't get the Berger's to fly. I will keep working on the Noslers and the Hornady's. I will let you know how it progresses.

 

[Snowrun]

Using Reloader33 based on advice from this forum. Going to do a bit more workup, but now at 2720fps, very accurate and single digit variation. 96.5 grains in Nosler Brass, takes 97.5 in Bertram brass to match velocity/performance.
Also, this is for the 285 grain ELD-M(match). I have not seen ELD-X nor LR accubonds in 338 cal., I would like to see both of these offered, maybe I'm behind the curve.

 

[JBMdc]

Does anyone else have any load data for the 285 AMAX or ELD-M??

Right now I am pushing 300 Berger Hybrids 2645 with 87.6gr h1000, but looking to make the switch to the Hornady bullets. Just not sure how much higher I can go with this powder bullet combination.

I never looked for a max pressure with my current configuration.

 

[D.Camilleri]

I have a new barrel this year and I have only shot RL33 with both 300 gr Berger OTM's and 300 gr Nosler Accubonds. Both shoot under 1/2 moa with 99 grs with the same point of impact. The Bergers are seated to 3.800 oal and the accubonds to 3.720. Bergers velocity is 2805 and accubonds are 2790+-

 

[aramarine6]

Wow 2805 with 300 grain bergers? I'm going to have to give RL33 a try. I have some loaded up with Retumbo for testing. I dont think I'll get that kind of speed though.