300 win mag 22" barrel

[montgomery627]

First off, I may be posting this in the wrong section and I'm sorry if I am.
I just had my 700p 300 Win Mag barrel cut down to 22". I want to be able to move it around in a deer stand a little easier. I'm starting to second guess what I did. The smith called and said that the gun is finished so, I will be picking it up tomorrow and start working on working up a load for it come Tuesday. I have been shooting H-1000/208 combo and H-1000/190 SMK combos. I'm thinking that H-1000 will be a little to slow of a burning powder for the shorter barrel. I still want to shoot a 190 SMK out of it if possible. I also have a bunch of 180gr Nosler AB that I shoot out of my WSM that I can swap over to. I have a bunch of RL-22,RL-19&RL-17 on hand along with a few other various powders. Wondering if anyone has had their WM barrel cut down to 22" and if they have came up with a good load for theirs. Any help will be greatly appreciated.

 

[Carrbque]

I have a 20" 300 WM and I love how handy she is. Here are some notes from my early load development, I have since landed on 74.4 grains of Ramshot Magnum and 230gr Berger Hybrids. Very accurate in my rifle and packs a punch on the other end. Just be sure to develop loads slowly and carefully! Stop shooting if you notice any pressure signs!

Elevation: 5791
Temp: 51'F
Started at 65.0 and increased by .2 grains until max load at 74.0 then a few above max loads at 70.8
At max this load showed no signs of pressure and is only 97% full.

65.0 was in the high 2200's and gradually climbed to 2480's at 70.8 gr.
this load really started to impress after 72.0 gr. which was 2540.

I MUST ADVISE THIS LOAD IS WAY OVER MAX !!

At 74.4 I am getting 2590's to 2610. At those velocities I go subsonic at 1630yds and at 1170yds i am at 1009 ft-lbs of energy on target.

Hope this helps, just remember to develop for your rifle, as they are all different.

 

[jagged77]

I had mine cut back to 24" to make it a little more handy plus rethreading. VV N165 plus 208 Amax work extremely well and I'm sure would continue to do so if I cut back to 20"

 

[Carrbque]

I had several over pressure signs with H-1000 in a 20" barrel, I also couldn't get very good velocity with such a short barrel.
Every rifle is different and H-1000 is an awesome powder and might be a good powder to add into your testing.

 

[montgomery627]

Thanks for the input. Have only tried RL-22 so far with a 190gr SMK. 70.5 grns will shoot a .491 3-shot @ 100yds. Haven't ran it across a Chrono yet to check the speed. Was running low on H-1000 after loading up my 7mm STW for hunting season. Powder Valley had gotten some in last week so, I ordered 10 lbs. It just came in yesterday so, Monday while I'm off I'll load some up with it and try them out.

Thanks again for the input.

 

[RyeDaddy]

I'd be interested to hear your results with H1000 in the 22" barrel when you get around to it. Contemplating a 5R in 300 WM now to have cut back to 22" and threaded. I was wanting to use h1000 and 208 Amax's with it for general long range shooting and hunting.

 

[Fuzzball]

Your peak chamber pressure will occur at about 3 inches of bullet travel so what ever powder gave you the best speed before will still do so.

Muzzle blast will increase, speed will decrease and your best accuracy load may change a bit but you already knew all that.

 

[shoot4fun]

How about IMR4350? It worked well for me paired with 190SMK in a 26" barrel and is slightly faster than H1000 IIRC.
H1000 will work and if that is all you have I wouldn't worry. Muzzle blast is going to be worse any way due to the shorter barrel.

 

[81sfo]

I'm running a 22" Obermeyer tight bore on my 300 win mag. I found real good accuracy at 75.8 h1000 with the 208s win primer black hills once fired brass, but I'm at 2650 fps. I will be going up in charge to see if I can find the next accuracy node. Shot three 77.1 grns h1000 that showed some promising accuracy at 2785fps.no pressures yet.