# Update on my latest 300WSM build.



## longbow (Mar 31, 2009)

I found a spent case in a clearcut a few months ago. Like every guy with a bad case of reloader's disease, I picked it up. Hmmmm, it's a 300WSM. Now that's a caliber I don't have. I also need a longeranger that is cheaper to shoot than my bigger calibers. 
I thought about a NIB Rem700 short action and barrel I had at home that was meant for some sort of standard 30 cal. I just needed a bolt with a magnum bolt face, stock, recoil lug, bottom metal and a few other odds and ends and I'd be in business.
So after much online shopping, I sent off orders to Pacific Tool and Gauge, Stockys Stocks, Numrich, Tactical Works, Brownells and Midway USA. Before long I had a pile of gun parts.
Luckily Alaska Game and Fish has a lathe that has seen very little use in years. It's old but everything is still tight.
Here's a short rundown for those who are interested:

The first thing I did was drill holes in the tailpiece and install these brass screws to align the back end of the barrel with the four-jaw chuck. I forgot to take a picture until I got the chamber done.









Here's some of the parts. I made a tapered "tool" (B) to measure the exact bore diameter at the muzzle. I put this into the barrel until it fit snug and then I used that to make another "tool" (A) to shove into the muzzle so I could index off of that. I can explain them better if anyone wants to know. (C) is my go-gauge. If you're wondering what (D) is, it's marks on my barrel from a copper shim to protect my barrel from the chuck jaws.









Here's how I indexed the chamber end. I used this aluminum rod to align the bore with the chuck. Then I bent the tip so it would ride against the chamber to make sure it was aligned with the bore. It was. This was a short-chambered barrel so I had to thread and cut the tenon for a .250 recoil lug, then finish the chamber to spec with a finishing reamer. I spent 95% of the time aligning the barrel until the dial indicator needle barely moved when I rotated the chuck. I almost went crazy during this step. I wanted my barrel to be faced perfectly with my action.









Next, I turned the barrel around and threaded the muzzle for a Vais muzzle brake. Again, it took me 95% of the time to get it aligned. It turned out perfectly aligned with the barrel but I cleaned off the burrs on the muzzle side a bit too much and it left a sloppy looking seam. It bugs me. 
I have several guns with Vais brakes and I've loved them. For big calibers I prefer the big side-port brakes.









Here it is assembled.









Now the barreled action is nestled in a Stockys Classic stock while the glass bedding cures. I really wished I'd taken a picture of the bed when I first pulled it out. I've bedded quite a few actions and this was the very best I've done. I was proud.









Here's the finished gun...well almost. I have a NightForce 3.5-15x50 NP-R2 on the way but I ain't waiting for it so I stole a 6-18x44 scope and rings off my 204Ruger.









I took it out with a bunch of test loads and had a fit. Everything I shot showed high pressure signs. I went through everything I could think of and couldn't figure it out. Finally I called out for help from the UWF and LongRangeHunting. I missed something on this build. I didn't think about the 300WSM having a rebated rim. The bolt face needed to be machined different. I spent hours making a jig out of an aluminum block to mount my bolt in the lathe. I modified my bolt to specs and headed back into the clearcuts to try again. This time I was happy.









I shot an Audett ladder with IMR 4350 and a couple W760 loads with 168gr A-Max just pressing against the lands. The IMR4350 loads made a nice cluster with the 64.0 - 67.0 loads. I yanked a shot on the 65.0 load but I'm sure it would have been in there with the rest. All loads were shot at 211 yards and, with the exception of the 65.0 load, were between 1 - 1.5 inches. I'm going to go with the 66.0 since it's in the middle of the node. I'm still going to mess a bit with my OAL but at 211 yards, I'm happy with how it shoots as it is.


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## waspocrew (Nov 26, 2011)

Sounds like it was a pretty fun project - glad to hear you got the source of the pressure signs squared away!


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## wyogoob (Sep 7, 2007)

impressive work

.


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## swbuckmaster (Sep 14, 2007)

Skills. Man's got skills.


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