300 WSM Medium Action Build input

[N8Nobull]

Looks great
You should have no problem getting to 2800 fps with h4350 which is great for the 300 wsm

Are you running a SAAMI spec chamber, or a long throat? I'm curious if a slower burn powder like H4831 would benefit more with the greater case capacity since the bullet isn't seated as deep.

 

[Marky_mark]

mine is throated long. h4350 is sneaky good for a 300 wsm. Incredibly consistant

 

[bghunter20]

When I built my 300wsm (Hells Canyon Armory), I saw a post from Alex Wheeler -> ".220-.230 fb range is where I go with the 215s", referencing the 215 bergers. I ended up with .228, and pretty happy with it. I run the the 182 tipped hammers at 3100fps in a 20" barrel. They seat really long and leave a lot of case capacity.

I'm working on a 300 wsm build right now hoping to accomplish the same numbers with the same barrel length and bullet. Would you mind providing the details on this build?

 

[N8Nobull]

Big Horn/ Zermatt Origin medium action, 22" 1:10 twist Proof Research M24 fluted by LRI and chambered by Red Desert Rifles. Manners EH1 stock, also bedded by Red Desert Rifles. Trigger Tech special 2-stage with Hawkins Precision XM+ bottom metal and magazine. I'm not sure of the exact chamber specs as far as free bore goes, but I just supplied a dummy round with my intended bullet and seating depth, and he used a throat reamer to get it to fit. Right now I'm still working on load development with the 200gr ELD-X but haven't got to shoot them yet. I have done some preliminary testing/ break in/ fireforming with 195gr ELD-M, CCI250, 61gr of Reloder 17 and got 2780fps. Now according to GRT, I have room to go on this combo, up to ~63gr of Re17, and should be above 2850fps.

 

[AZShooter]

I made a load for a friend's Browning A-bolt with the boss years ago. 230 gr Berger and RL-17 from his 22" barrel with the mag box constraint of 2.8", 2725 fps.

I posted the picture years ago here and elsewhere. The running joke was the base of the bullet was sitting on the flash hole. Anyway it was accurate and lethal. My friend shot his last elk with it at 300 yds.

 

[huntinfool18]

66gr of h4831 and a 205berger is right at 2800 in my 22" wsm. Touching the lands at 3.150". It max in my rifle, work up to it if you try it.

 

[JAYgs8163]

I'm working on a 300 wsm build right now hoping to accomplish the same numbers with the same barrel length and bullet. Would you mind providing the details on this build?

Tried to send you a PM but was unable. Looks like you either are blocking people or have no privileges yet.

 

[Justice1327]

I finally got my barrel back from LRI, and I am utterly impressed. This fluting cut out a ton of weight! Action and barrel are at Red Desert Rifles to get spun up now. I gave Chad a dummy round with a 205 Berger EH seated at 3.150 COAL for chamber dimensions. All I need now is a stock and she'll be ready to run once Chad gets it chambered. I'd really like to find a Manners LRH or maybe a McMillan Game Hunter or Scout.

View attachment 607607

Great looking Rifle. I'm just curious why would you not have Chad at LRI chamber thread and assemble it while he had it doing the flute

 

[Laguna Freak]

I am currently in the process of building a 300 WSM. I have a SS Proof M24 1:10T currently at LRI to get the murder hornet fluting done and a Zermatt/Big Horn Origin Medium length with Hawkins DBM and mag on the way. I know I am a little restricted with how heavy bullet I can run with the 1:10" twist, but I plan on having the barrel at 22" and hoping to be in the 2800fps range. I figure I'll run 190-210gr projectiles, such as the 190 ABLR, 195 ELD-M, 200gr ELD-X, and 205gr Elite Hunters.

Curious on input if I'm on the right track, and what freebore or reamer specs might be recommended for this setup.

This is also the first forum I've signed up to be on, so I'm a rookie to this, but I have built several custom rifles, so I'm not totally ignorant.

Thanks,
Nate

I shoot two 300 WSM, LA and SA. I think you'll be fine with 1:10 twist and bullets 205 gr and less. You should run your data through some ballistics and stability calculators. I prefer JBM. I use a 1:8.5 twist for bullets 200 gr +. I built with the 1:8.5 due to a "fear" that I may only be able to buy mono's at some future date.

 

[bghunter20]

Tried to send you a PM but was unable. Looks like you either are blocking people or have no privileges yet.

Yeah I don't have the privileges yet, I'll PM you whenever I get them

 

[N8Nobull]

Great looking Rifle. I'm just curious why would you not have Chad at LRI chamber thread and assemble it while he had it doing the flute

I didn't have the action yet. All I had was the barrel and he said he wouldn't do a pre fit

 

[JPatzig]

I'm working on a 300 wsm build right now hoping to accomplish the same numbers with the same barrel length and bullet. Would you mind providing the details on this build?

Defiance AnTi long action
Hells Canyon Armory 20" Carbon Fiber barrel, Tactical contour, .228 freebore, 1:9.5 twist. He used a Benchmark blank for the barrel.
AG Composites Privateer (Action bedded)
TiggerTech Diamond
M5 Oberndorf Bottom Metal
Wyatts box for WSM
I run a TBAC Dominus CB suppressor

Load:
182HHT
RL16 - 66.0Gr
CCI 250
ADG Brass
OAL 3.160
.304 mandrel
Light Lee FCD crimp