33 SHERMAN MAGNUM

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The new 33 Sherman Magnum is here and ready to be spun up and ready for elk season. It is based on the 30 SM simply necked up. This baby promises to be a Hammer and the 28 and 30 versions have shown outstanding accuracy!
No data yet but you can be the first. I expect the 285 to reach 2800-2850' and it will likely run a 250 Berger to 3100'.
Phil Allen has the reamer and Hornady is currently cutting dies.
This will be a very strong performer on a std magnum bolt and no rebated rim.

Phil Allen
MCM Firearms
www.mcmfirearms.com
208-406-5000
Looks kind of similar to the 330 Dakota. Very good round!!
 
Out of curiosity, what kind of barrel life do you get shooting close to 100 grains of powder every time you pull the trigger?
I have no experience with this. My largest rifle is a .280AI shooting close to 60grains of H4831sc.
 
If ya got time, pin that bad boy too. #31 drill, through the rail into the reciever, just not all the way through, between the screw holes. Measure how deep, then cut some pieces of a 1/8" drill bit to match the depth, put a dab of lock tight on them and tap them into the holes. The hole is .120", and hardened tool steel drill bits, or pins, are .125", so make a nice pressed fit. That rail won't go anywhere!
Cody, What do you consider the minimum required depth of the #31 drilled receiver hole? Excellent project idea! I noted Gunwerks pinned the base(s) on my ClymR 7 SAUM. My next project is Rem 700 LH LA .338 RUM. Your tip is perfect timing! T/U, Jasbo
 
Out of curiosity, what kind of barrel life do you get shooting close to 100 grains of powder every time you pull the trigger?
I have no experience with this. My largest rifle is a .280AI shooting close to 60grains of H4831sc.
The 33SM won't hold 100grains of powder, more like mid 80s. 99gr H2O with no bullet. But to your point, 338 is a big bore and that is a large part of the barrel life equation. With proper cleaning and shooting, I'd say 1500-2000 rounds is safe with this round. 338 Win Mag (70gr powder) guys I know are claiming 3000, and it seems like 338 Edge (100gr powder) life is right at 1000.
 
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Cody, What do you consider the minimum required depth of the #31 drilled receiver hole? Excellent project idea! I noted Gunwerks pinned the base(s) on my ClymR 7 SAUM. My next project is Rem 700 LH LA .338 RUM. Your tip is perfect timing! T/U, Jasbo
I personally just went with about 2/3 the way through the reciever where I put the pins.
 
Sorry, I'm using Peterson. No complaints with it tho.

Good to know still, thankyou for sharing. The reason I was asking is, I "think" the Lapua Brass has a slightly thicker neck than the ADG Brass that the Reamers were spec'd out with. Peterson is usually thicker than ADG too, so it's probably just fine then.
 
Hey guys!

What have you used for a fire forming load? Projectile weight/model & powder charge/type please 😁

I've got a bunch of 230 ELDX & an old lot of H1000 I'm going to use for fire forming. Open to any suggestions, and of course "start low and work up, standard disclosure..."

Thanks!
 
I'd look at 338 rum data for the 230 and take 10% off a mid load since the 33 sm is 10-11 grains less capacity than the rum which happens to be 10% between them.

Might want to move to a slightly faster powder possibly.

Or you can get the nosler data for the 225 ab for the 33 nosler and pick a mid load with that. The capacity difference between these two is 4-5 grains (more for sm when formed) which may be a better place to start than down loading rum data.
 
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