My 338 Sherman Shortmag

[tdot]

It'll be awhile. Rifle has been shipped back to the gunsmith for additional throating.

I havent had my notes with me for awhile. But I did see some additional speed with decreasing the neck tension to .001". It was roughly an additional 100fps and I didnt hit pressure. Havent been back to try again.

I also saw about a 100fps increase from changing the primer to a CCI BR2, from the Fed215M, but did hit pressure.

I did not combine those two changes, so dont know if there was even more velocity available.

Thanks again for that suggestion! I stopped playing with neck tension awhile ago, as I always seemed to settle on .002 and the extra testing wasnt worth it. But it sure is worth it with this cartridge.

 

[ramrod79]

What are you sizing your necks to I use a 362 bushing.

 

[tdot]

What are you sizing your necks to I use a 362 bushing.

I use a separate carbide mandrel to size the necks. I find it an easier system to utilize overall. So dont bother with messing with bushings or expander balls anymore.

 

[ruby76]

Rifle has been shipped back to the gunsmith for additional throating.

I just got mine back, did the same thing. With the 250 berger OTM, CBTO touching lands is now 2.182, COAL of 3.036. With the 230 ELDX CBTO is now 2.156, COAL of 2.898. I added about .120 ish over the standard throat reamer. I'm now starting over with testing and loaded up some 230's with H1000, H4350, and Varget.

 

[ramrod79]

I use a separate carbide mandrel to size the necks. I find it an easier system to utilize overall. So dont bother with messing with bushings or expander balls anymore.

I would like to see your die that sounds like a slick set up.

 

[tdot]

I would like to see your die that sounds like a slick set up.

It's a Sinclair Die. I believe that 21st Century also makes a similar die.

GENERATION II EXPANDER DIES | Brownells

Our Generation II Expander Dies completely capture the mandrel within the die so the mandrel cannot pull out. An O-ring in the die cap allows the mandrel to float a bit and find its own center within the case neck. All three Generation II dies are...

www.brownells.com

Neck Turning mandrels are .002 under caliber and Expander Mandrels are .001 under caliber. I prefer carbide, alot more expensive, but 100% worth it.

It makes the resizing process easier and more consistent. It also made the brass prep for the 338ss from 6.5mm to 338 alot easier.

 

[WiscGunner]

It's a Sinclair Die. I believe that 21st Century also makes a similar die.

GENERATION II EXPANDER DIES | Brownells

Our Generation II Expander Dies completely capture the mandrel within the die so the mandrel cannot pull out. An O-ring in the die cap allows the mandrel to float a bit and find its own center within the case neck. All three Generation II dies are...

www.brownells.com

Neck Turning mandrels are .002 under caliber and Expander Mandrels are .001 under caliber. I prefer carbide, alot more expensive, but 100% worth it.

It makes the resizing process easier and more consistent. It also made the brass prep for the 338ss from 6.5mm to 338 alot easier.

I run the Sinclair die with both mandrels as well in my Forster. Love this set up and see no reason to do it another way.

 

[tdot]

I just got mine back, did the same thing. With the 250 berger OTM, CBTO touching lands is now 2.182, COAL of 3.036. With the 230 ELDX CBTO is now 2.156, COAL of 2.898. I added about .120 ish over the standard throat reamer. I'm now starting over with testing and loaded up some 230's with H1000, H4350, and Varget.

Have you had time to work on loads with the longer throating? Results?

 

[ruby76]

Have you had time to work on loads with the longer throating? Results?

No, not yet, like many we've been barely leaving the house lately. Have the first batch loaded and ready to shoot. All I've done is fireform 338SS headstamped brass a while back.

 

[drgalan]

Your gonna love the results you get!

 

[TexasTB]

Hope everyone is having a good summer. I'm running my 338 SS with 230 g ELDX with 61.7g of Varget out of my 22" Barrel at 2900 fps. I'm almost out of Varget with no supply in sight. Anyone using IMR 4166?

Thanks

 

[drgalan]

I just bought 3 more pounds at a local gun shop in Claremore, Ok (Bill Sporting Goods)
Hope that helps.

 

[codyadams]

Hope everyone is having a good summer. I'm running my 338 SS with 230 g ELDX with 61.7g of Varget out of my 22" Barrel at 2900 fps. I'm almost out of Varget with no supply in sight. Anyone using IMR 4166?

Thanks

3rdgss recently had a shipment of varget. Just get several powder suppliers, powder valley, 3gss, graffs, and a couple others, and check them daily, and if you jave one, follow them on facebook, and you will eventually find it in stock, probably within 1-2 months, maybe less.

 

[ruby76]

Guys with a 338 SS, could you please measure your outside neck diameter with a fired case please. As well, diameter at web near base. Chasing some pressure / sticky case issues. Thanks