McGuire 168 300wsm load data

[Crnaduckman]

I should have my new build anyday. Unknown munitions 300wsm +P 18" peak 44 stock. I ordered a few hundred of the 168 McGuire copper rose and adg brass. I have another custom 300wsm so I have a bunch of loading experience for the caliber. Hoping someone has some insight for what the bullet likes, powder? And jump? I was thinking probably H4350 and starting around 30 thousandths off. If anyone has experience with the bullet and wants to share some results please share. I was going to use 168ttsx load data as a starting point.

 

[SnakeRiverEric]

Which 168 the standard or long version? In my 300wsm with the old standard version, 24" barrel running 62.3 gr H4350 at 0.010 off. Using F215 and ADG brass 3030fps, N550 61.5-62.0 yields 3120fps. WIth your shorter barrel would start lower and 0.020-0.030 off as you said.
Have fun.

 

[Crnaduckman]

Thank you exactly the type of info I was looking for. I am not really sure. When I ordered the bullet they asked me if I would be magazine feeding and I said yes. So maybe they are the short version. I have plenty of magazine capacity so maybe I should send them back for the others?

 

[SnakeRiverEric]

The Long version has a bigger cavity behind the tip and is longer in length, has better BC than the standard. What twist is your barrel? I have a rebarrel going on right now on a different rifle with 1-9 twist hoping to run the Longs, 178's and 195s. It has the Unknown DBM so I can load them long too. Break your barrel in using the standards and then try the Longs, etc.

 

[Crnaduckman]

i bought enough of them that I'll be halfway through the barrel before switching. The higher bc and lower expansion velocity seems like a no brainer to try to swap out. I'm going to ask if they will allow me to swap the unopened ones out. Rifle will have plenty of twist. I don't have it in hand yet waiting on stock, but I am 90 percent sure they UM recommended an 8 twist. I suggested 9, but they said they had a lot of experience with the bullet and 8 was right. I asked them to do whatever was best for that combo.

 

[SnakeRiverEric]

Yes, you will be fine with the 8 twist, I am able to shoot the 195s with my 10 twist here in Wyoming (at altitude 6200ft) in my 300win.

 

[Crnaduckman]

I have never used N550 before. Is it temperature sensitive? Were you getting similar accuracy and sd compared to 4350? Or was 4350 easier to work with? Which did you prefer?

 

[SnakeRiverEric]

Sam has more experience with 300WSM than me. My gun is an old Savage that mostly sits in
back of my safe. I was experimenting with it, and Sam said to try both, he started with 4350.
Then I tried a ladder of N550. With 4350 went 61.5 to 63.5, went from 2996 to 3081, first 4 shots ragged hole, 5th an inch higher at 200yds, 62-62.5 were 3037 each. Don't have sd's available but probably single digit. For N550, 61.5 to 63.5, went from 3118 to 3210 (clicker), first shot slightly right of remaining 4, 2" inch high at 200, sub MOA group. 61.5 3118 62 3124.
Not sure on temp sensitivity. Sure 4350 is better in that regard.

 

[Crnaduckman]

Eric thank you so much for all the info. I'll run a ladder with 4350 and see what velocity I can get. If it's mmm

Sam has more experience with 300WSM than me. My gun is an old Savage that mostly sits in
back of my safe. I was experimenting with it, and Sam said to try both, he started with 4350.
Then I tried a ladder of N550. With 4350 went 61.5 to 63.5, went from 2996 to 3081, first 4 shots ragged hole, 5th an inch higher at 200yds, 62-62.5 were 3037 each. Don't have sd's available but probably single digit. For N550, 61.5 to 63.5, went from 3118 to 3210 (clicker), first shot slightly right of remaining 4, 2" inch high at 200, sub MOA group. 61.5 3118 62 3124.
Not sure on temp sensitivity. Sure 4350 is better in that regard.

Sam has more experience with 300WSM than me. My gun is an old Savage that mostly sits in
back of my safe. I was experimenting with it, and Sam said to try both, he started with 4350.
Then I tried a ladder of N550. With 4350 went 61.5 to 63.5, went from 2996 to 3081, first 4 shots ragged hole, 5th an inch higher at 200yds, 62-62.5 were 3037 each. Don't have sd's available but probably single digit. For N550, 61.5 to 63.5, went from 3118 to 3210 (clicker), first shot slightly right of remaining 4, 2" inch high at 200, sub MOA group. 61.5 3118 62 3124.
Not sure on temp sensitivity. Sure 4350 is better in that regard.

If it's looking slow maybe I'll try some nv550. I know I need to get the most I can with the short barrel. That bullet needs quit a bit of velocity to expand. Maybe the plus P chamber with help with the speed.