My Winchester m70 in 7mm wsm is throated short and is leaving .185" free in the magazine and forcing the 168gr berger classic hunters much farther into the case than is ideal. I'm thinking of ordering a 7mm throat reamer from ptg with a t handle and lengthening the throat. The rifle shoots pretty darn good as it sits and it would be a shame to wreck that but the seating depth is bugging me. Has anyone here done this and how did it work out. I'm probably going to do it anyway but wanted others experiences and any heads up they can give. Worst thing that could happen is I have the 3 groove 9 twist in the corner installed when I wreck the factory barrel. Anybody want to share their experience and the finer points to look for ?
Lengthening the throat DIY results ?
- Thread starter Daveinjax
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shortgrass
Well-Known Member
Order your reamer and handle and make sure you've got a 'smith lined up to install your new barrel.. Better yet, why not take it to someone who knows how, to begin with?
Two reasons for doing this myself. First is that I like to work on my rifles and second is that I can't find a smith in town who I trust. The other problem I have run into with the local smiths is the reluctance to do what I want done and not what they want to do. For example , I want my trigger set around 16oz and no more than 20oz on my hunting rifles. Answer from smith was you don't need less than 2lbs . I now do all my own trigger work and I like all my triggers. If I had the spare cash I would have my own lathe and be doing 100% of the work on all my rifles. I have butchered a few things while teaching myself but I have never regretted any of my efforts. If I buy a new barrel after this effort then so be it. Next up for me is installing my own pre chambered barrels and finishing them by hand. There is nothing too technical about any of this metal work and a few tricks and pointers passed on from more experienced hands has saved me from most mistakes. Even if I had the money to hire the best smiths in the business I wouldn't. I would just buy the best equipment and hire some good teachers. This is my hobby.
westcliffe01
Well-Known Member
If you have not already, take a look at Mansonreamers.com Small business in Southern MI, make excellent product. They are willing to talk to you about your project too. They have throating reamers on page 9 of their catalog.
Having a suitable depth throat is pretty key for best performance with high weight bullets. Just remember that your barrel may not be that good with lighter caliber bullets afterward. If doing it yourself, you may want to do this in stages (go 2/3 of what you think you can increase) and see how it works out. Nothing worse that going too far.... Seating the bullet further out will lower pressure and decrease velocity but your max load "should" be higher once you have broken in the new throat with the bullet seated further out.
Having a suitable depth throat is pretty key for best performance with high weight bullets. Just remember that your barrel may not be that good with lighter caliber bullets afterward. If doing it yourself, you may want to do this in stages (go 2/3 of what you think you can increase) and see how it works out. Nothing worse that going too far.... Seating the bullet further out will lower pressure and decrease velocity but your max load "should" be higher once you have broken in the new throat with the bullet seated further out.
Westcliffe01 , thanks. I'm well aware of the bullet weight and throat lenght dynamics. I've got a 7mm-08 spitting the 140gr berger vlds great and the 7mm wsm is my elk rifle and will never shoot anything lighter. The great thing about doing it myself is that I can cut a little and try then cut a little more until I get it where I want. This barrel is not going to be on this action too much longer anyways. Like I said , there is a three groove lilja sitting in the corner waiting for money and a reason.
catskinner
Active Member
You are thinkng the right way. Most people are afraid and think they can't do it. Once you do it you realize it was harder thinking about it. Plus by the time you get the smith to get it done you may be dead. And you will start adding tools to your bench that will pay off in the future. Always, always, always buy quality though. I'm sure you know that already it sounds like.
Thanks catskinner , l'm going to order both a 7mm throat reamer and a full finish reamer in 7mm-300 wsm so I can do the new barrel too when time comes. If I could luck into a mint Monarch 10EE for a couple hundred dollars at a garage sale I'd be set ! I can dream at least 
.
.catskinner
Active Member
Goodluck. To bad you are so far, I'd let you come play on my grizzly. Wish I had a monarch
