300 Sherman Shortmag (SS)

Okay - after reading this thread I am VERY interested. I was going to build a 300WM or WSM but then I stumbled across this. I want to build a decently light magnum rifle and still be able to run my can (Saker). It is rated to 300WM so it should be fine with 300SS.

This left hand stock is for sale in the threads....

https://www.longrangehunting.com/threads/manners-compact-stock-lefty.241227/ (yes, I am a lefty).

I am trying to determine if the magazine with that set up will work with the 300SS AOL or is there a magazine out there that fits that manners mag well and still cycle the 300SS without sacrificing performance due to mag length limitations. Normally I'd go to the gun parts store or speak with a smith but currently stuck in Italy for 2.5 more years until I retire from the Navy. This rifle will be my retirement "gift" ;) .

I don't have any true wildcats but reload for all of my other calibers. Always wanted something not a lot of folks have and the performance on this short mag seems to be there (great work by the way).

Could use some advice on Mag/COAL compatibility when it comes to feeding. I haven't purchased and an action or barrel yet but was looking at lone peak TI or Big Horn with a proof Carbon Sendaro or light. Also looking for recommendations.

Thanks.

The first question you should ask yourself is whether you want to run detachable magazines or an internal magazine. This willnarrow down your cartridge length options. The stock you have linked fits a 700 Short Action and has an internal aluminum chassis that fits AICS magazines. ARC, Alpha and A curate magazines tend tohave the longest internal cartridge length from the factory. 2.95 to 2.97". This Pprticular stock is not a good one for modifying to use a longer magazine. You may order it directly from Manners with other options that may better suit you needs if wanting a long action, internal magazine, etc.
FYI I run my 7SS in ARC magazines at 2.945.

It is important to remember the benefit of using a short action is NOT velocity although Sherman cartridges are designed to maximize a short action if that is what you have. I run a short action because I want to shoot other short action cartridges in a switch barrel setup. If you want more length or speed than 700SA offers consider the MAX cartridge family in a Tikka or a 300SM in a full length action.
 
Ok Rich, has anyone used the 110 FB reamer yet? If not I guess I will be the first. I have a barrel headed my way and an order on your website waiting to pay for it. Just need to find some projectiles.
 
Has anyone run the 300 SS in a 22" barrel with any of the 200 gr bullets?

Looking to build a handy short mag. I like the on game performance of the 30 cal bullets like the 215 hybrid but need to be 2.96 oal for mag so maybe a 200 hybrid? Otherwise the 180 hybrids in the 7ss are very appealing ballistically.
Thanks.
 
Has anyone run the 300 SS in a 22" barrel with any of the 200 gr bullets?

Looking to build a handy short mag. I like the on game performance of the 30 cal bullets like the 215 hybrid but need to be 2.96 oal for mag so maybe a 200 hybrid? Otherwise the 180 hybrids in the 7ss are very appealing ballistically.
Thanks.
A 22" barrel should run a 200 at 2850-2900
 
Ok Rich, has anyone used the 110 FB reamer yet? If not I guess I will be the first. I have a barrel headed my way and an order on your website waiting to pay for it. Just need to find some projectiles.
Has anyone run the 300 SS in a 22" barrel with any of the 200 gr bullets?

Looking to build a handy short mag. I like the on game performance of the 30 cal bullets like the 215 hybrid but need to be 2.96 oal for mag so maybe a 200 hybrid? Otherwise the 180 hybrids in the 7ss are very appealing ballistically.
Thanks.
I have this build right now you are all referring to, just waiting for it to come back home in the next couple weeks to start load development:
- LPA Razor Ti Short Action, milled for the 3.110" PTG 3B Bainey Box by LRI.
- 300 SS, Proof Carbon Fiber, finished at 22", chambered by Lane Precision Rifles.
- Manners EH4, GAP Camo, pillar bed by LRI.
- Cerakoted Desert Verde, bolt nitrided (black) by LRI.
- Nightforce NX8, 4-32 F2.
- TBAC Ultra 7

I'll start a thread on my load development, planning on:
Powders - N560, N555, N550, HV100, and H1000.
Bullets - Berger 200 and 215 Hybrids
 
I have this build right now you are all referring to, just waiting for it to come back home in the next couple weeks to start load development:
- LPA Razor Ti Short Action, milled for the 3.110" PTG 3B Bainey Box by LRI.
- 300 SS, Proof Carbon Fiber, finished at 22", chambered by Lane Precision Rifles.
- Manners EH4, GAP Camo, pillar bed by LRI.
- Cerakoted Desert Verde, bolt nitrided (black) by LRI.
- Nightforce NX8, 4-32 F2.
- TBAC Ultra 7

I'll start a thread on my load development, planning on:
Powders - N560, N555, N550, and HV100
Bullets - Berger 200 and 215 Hybrids
Good deal, mine is a bartlein carbon at 25", and will be together Monday. I'm going to test 100V, H4350, and H4831sc. Bullets are Hornady 208, 212, 220, 225, and the Berger 215, but I doubt I will even mess with the Bergers.
 
The first question you should ask yourself is whether you want to run detachable magazines or an internal magazine. This willnarrow down your cartridge length options. The stock you have linked fits a 700 Short Action and has an internal aluminum chassis that fits AICS magazines. ARC, Alpha and A curate magazines tend tohave the longest internal cartridge length from the factory. 2.95 to 2.97". This Pprticular stock is not a good one for modifying to use a longer magazine. You may order it directly from Manners with other options that may better suit you needs if wanting a long action, internal magazine, etc.
FYI I run my 7SS in ARC magazines at 2.945.

It is important to remember the benefit of using a short action is NOT velocity although Sherman cartridges are designed to maximize a short action if that is what you have. I run a short action because I want to shoot other short action cartridges in a switch barrel setup. If you want more length or speed than 700SA offers consider the MAX cartridge family in a Tikka or a 300SM in a full length action.
This is the deciding reason I had my Razor Ti SA milled to a Bainey Box length. I also run a 6.5 SAUM throated for the Berger 156's and have a 22" 7 MAX barrel coming, both from Lane Precision Rifles. I switch out my shouldered barrels using a Short Action Precision Modular barrel vise.
 
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Good deal, mine is a bartlein carbon at 25", and will be together Monday. I'm going to test 100V, H4350, and H4831sc. Bullets are Hornady 208, 212, 220, 225, and the Berger 215, but I doubt I will even mess with the Bergers.
I'll buy all your Berger 215s if you're ever selling them.
 
Finally arrived and ready to start load development.
20210530_134455.jpg

20210530_134543.jpg

- LPA Razor Ti, milled for the 3.110" PTG "3B Bainey", 3-round Canoe BDL
- Manners EH4 Elite TAC, GAP Camo, pillar bed
- Calvin Elite Trigger (single stage)
- Proof Carbon Fiber, finished at 22" (pic)
- Also a 6.5 SAUM (throated for the Berger 156 EOL), Proof Carbon Fiber, finished at 24"
- Ti 5-port self-timing muzzle brake
- Cerakoted Desert Sage, bolt nitrided
- Nightforce NX8, 4-32 F2
- Tier One Carbon Bipod
- 7 lbs as pictured
 
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Good deal, mine is a bartlein carbon at 25", and will be together Monday. I'm going to test 100V, H4350, and H4831sc. Bullets are Hornady 208, 212, 220, 225, and the Berger 215, but I doubt I will even mess with the Bergers.
Have you had a chance to test any ladders yet?
 
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