Bolt action 308 Win to 300 WSM conversion

[375rifleman]

I was just wondering if anyone has ever taken a detachable magazine bolt action 308 Win and converted it to 300 WSM? Thanks in advance for any and all thoughts, opinions, and answers.

 

[shortgrass]

It'll work. Have the bolt faced opened to magnum dimentions and a M16 or Mini M16 extractor installed and get a mag box for the WSM. Feed rails might need to be opened to allow the new mag to latch into place and feed correctly. It'd have to be an awfull good factory barrel to warrant rechambering.

 

[LoneTraveler]

I agree with Short Grass. You would need a good barrel with enough chamber excess metal to allow the chamber to be bored out .085 (Eighty Five Thousands) to fit the 300 WSM cartridge, You did not name the gun, So it may take major extractor work, feed rail opening. Don't want to throw water on your dream fire. I thought about converting a 78 Rem. 308 Win. to 300WSM when the cartridge came out. After checking all the work I calculated and cost. my 308 Win. has a rack buddy a 300 WSM sitting bedside it now. I know Kimber completely redesigned their 84 rifle action into the 8400 action series to facilitate the Winchester short mag series. Good Luck

 

[BountyHunter]

You can but NOT a good choice for money spent doing all that! Sell the gun and buy a WSM.

You will be way ahead $ wise unless you are a smith and can do your own labor!

Bottom line is do not do it!

 

[375rifleman]

Actually I really like a rifle action but the rifle only comes in 308 Winchester kind of backwards of what you're saying. I like the action but don't like the factory barrel as it's in 308 Winchester and chrome lined which isn't to great from an accuracy standpoint. I also wasn't going to go with a straight 300 WSM either but rather a wildcat based on the 300 WSM. The rifle is a COC( or Cock On Close) Lee Enfield No.4 Variant the manufacturer is Australian International Arms No.4 MK 10 although I'm not entirely sure that I can get this rifle in the United States.

 

[LRSickle]

I just got done with a 308 Win to 300WSM conversion. I had to buy a new PTG bolt with a mag boltface. I could have opened the origional boltface but saved it for another build. I bought another barrel because I didn't think my sporter barrel had enough meat to set my tennon back to 300WSM length. My feed rails also needed work to feed the fat cases reliably.

Next time, if I'm hellbent on a 300WSM, I'll buy a 300WSM and true up the action/barrel/bolt and bed it in a solid stock. My new build shoots great but it was more work than it should have been.

 

[shortgrass]

The Lee Enfields are NOT suitable for the .300WSM or any other magnum cartridge. Split rear bridge, cock on closing, metallurgy not 'up to snuff', originally designed for the .303 British (which is a low pressure cartridge), the list goes on and on. Chrome lined barrels are not suitable for rechambering by most gunsmiths. Carbide tooling is required for such a task, high speed steel won't cut chrome. NO magazines available, for the Lee Enfield, that are suitable for the .300WSM even if the action was up to magnum capabilities. Very bad idea! Next time you post a question like this give more detail in your OP. You'll get better answers sooner.

 

[375rifleman]

I know that I should have said what I had planned for this rifle to begin with, and that enfields are not the strongest bolt action. I was just wondering considering it with what A-Square did with their Hannibal rifles which nearly all were chambered in some sort of magnum cartridge . I was/am going to replace the barrel regardless of the action that I end up starting with.

 

[shortgrass]

A-Square used Model 1914 "Enfield" actions and U.S. Model 1917 actions. Those are not even nearly the same as the Lee Enfields. The only thing they have in common is that the 1914 was designed at the Enfield plant. The British Government then contracted with U.S. firearms manufactures to build the rifles.The 1914 was re-designed by the U.S. Ordnance Dept. , upon the entry of the U.S.A. into WW1, to handle the Cal. 30 U.S. (.30/06) to make up for the shortages of U.S. 1903 Springfield Rifles during WW1. It was then designated Model 1917 by the Ordnance Dept. The Model 1917 & Model 1914 are massive actions capable of most any magnum chambering. I know of several who have built .30/.378 Wbys. using them. You have mistaken "apples" for "oranges".

 

[Wild_Bill]

Hi I have re barreled many smle rifles the no4 action is just strong enough for a 7.62 nato not a hot 308 win. If you run hot loads in a no4 you will get lug setback and action streach . The aia no4 rifles are actually made in india by ishapore they are beafed up a little and will handle the 308 win.

There is a reason they are made In 7.62x39 aswell as 303 british based wildcats.

If you want a heavy hitting smle or no4 rebarrel in 444 marlin they can work well.
They are not match grade actions and the rifles are very heavy aswell and you cant get a wsm compatable magazine aswell as the fact the first time you fired the rifle it would blow up.
I have a no1mk3☆ in 45acp that I made up shortening the bolt lenght and it takes 1911 mags great fun rifle also has an ar grip m4 butstock and ar free float tube.

So by all means use a smle action to make a fun rifle but a full loaded 308 based case is the max pressure for the strongest mk4 action.

Cheers Bill
Australia