.338 Sherman Short Mag build

[jsmitt6]

I like that a lot. I am probably looking at more like 2700 FPS with a 250 Berger. I just need to accept that. It is still a great velocity out of a true short action.

And at that is still a great velocity. Still gives me 1800 FPS and 1800 ft/lbs of energy at 1050 yards. *8000 ft is my average hunting altitude

 

[ruby76]

I like that a lot. I am probably looking at more like 2700 FPS with a 250 Berger. I just need to accept that. It is still a great velocity out of a true short action.

You may be pleasantly surprised with the 250 berger and H4350. I'm using a F215M primer and 62.5 grains. I'm going to do some testing with the 250.

 

[jsmitt6]

You may be pleasantly surprised with the 250 berger and H4350. I'm using a F215M primer and 62.5 grains. I'm going to do some testing with the 250.

I sure hope so. I have the ADG brass as well so it should be up to the task!

 

[jsmitt6]

Got my Defiance action back from my buddy this morning. Amazing how simple the fix was. Using a .25" end mill he went into the feed ramps and took off .125" in depth. Giving me more than .35" of clearance. Got the gun put back together (AGAIN!) and tested the feeding on 50 rounds. Each cleared the feed ramps and fed exactly how it should. I can't wait to go and start the load test for this rifle and see how that H4350 does.

@El Matavenados , sorry for basically hijacking this thread. I guess I could have started a new one, but think having some of these problems/experiences in one thread can help others that are possibly looking into joining the Sherman following.

 

[Earnhardt]

What is the freebore on the 338 SS?

What is the length of the Hornady 230 ELD-X? Bullet base to Ogive?

Anyone use the Hornady 338 SSTs in different weights?

Thanks

 

[elkaholic]

What is the freebore on the 338 SS?

What is the length of the Hornady 230 ELD-X? Bullet base to Ogive?

Anyone use the Hornady 338 SSTs in different weights?

Thanks

The FB on the STD reamer is pretty short because it was fitted to a 250 Berger.
230 eldx works well in a short barrel at over 2800'
I think FB is .083" on the STD reamer

 

[jsmitt6]

Hi All. Got back from the range. Here is the range report for H4350 shooting the 250 Berger Elite Hunter at an COAL 2.950. I was not finding any heavy bolt lift on any of these loads or primer cratering/ejector marks. I am also using the ADG brass. I was really wanting to get up to 2800 FPS, and believe that I could with a heavier load charge, but I fell in love with the accuracy of the 62 grain. I will be at 2725 fps for muzzle velocity and that gives me out to 1,050 yards to retain 1800 fps for proper expansion, well beyond what I typically shoot game at (usually a 500-600 yard kind of guy). I wanted to drop this here to piggy back on what Ruby had a few pages ago, in case anyone wanted to try H4350 and what they can expect for velocity.

Below are some of the groups I shot this morning. The first one that is labelled 61.5 is actually the 62 grain group. 3 shots in one ragged hole! Easily best group I have ever shot. I only did 3 round groups for this due to limited supplies of powder, primers, and bullets.

55.5grains
2429
2358
2409

56 grains
2440
2430
2444

56.5 grains
2433
2425
Error

57 grains
2450
2482
2485

57.5 grains
2540
2535
2414


58 grains
2566
2510
2485


58.5 grains
2610
2600
2590

59 grains
2588
2597
2575

59.5 grains
2627
2635
2615

60 grains
2653
2630
2643

60.5 grains
2683
2660
2673

61 grains
2680
2694
2698

61.5 grains
2718
2700
2700

62 grains
2716
2730
2733

 

[ruby76]

Good data, gives me a starting point. What primer are you using? I've found a noticeable increase in velocity with F215M over 210's. Are you limited by mag space and did you use the original shorter throat reamer? How far off the lands?

The unofficial "official" 338 SS thread for posting data has mostly been the thread I started and which is linked from Rich's website. There's a pile of testing and data there for all to see in one thread. Might be a good idea to post your data there, won't be highjacking.

 

[jsmitt6]

Good data, gives me a starting point. What primer are you using? I've found a noticeable increase in velocity with F215M over 210's. Are you limited by mag space and did you use the original shorter throat reamer? How far off the lands?

The unofficial "official" 338 SS thread for posting data has mostly been the thread I started and which is linked from Rich's website. There's a pile of testing and data there for all to see in one thread. Might be a good idea to post your data there, won't be highjacking.

I am using CCI Magnum Laregr Rifle 250 primers.

I am limited by mag space as well as the standard reamer. I believe I am .018 off of the lands, first time I have ever measured though.

I will post this over in that thread as well