Home Forums Hunting & Shooting Gunsmithing Converting a 99 in .308 to .358

I would love to have a 99 in .358 win, but they are rare, and expensive. Does it make sense to find a 300, or 308 to rebore? Will it hold the pressure, should it be rebarreled, or should I forget the whole thing??? Sunshinegirl

I had one, a 1969 model, glossy stock, no character, probably 98% condition, hated it's looks, and I sold it. Since then, I have have seen beautiful old ones that had the look of being carefully made, hand rubbed stock, and dearly want one. Don't, and won't want to rework one like that, but would find one that could use some help to be pretty again.

If you have a 99C, detachable clip magazine style, it is as easy as having an existing barrel with a smaller bore, rebored and rechambered.

If you have a rotary magazine 99 action, 99DL/E/F, you may need a 358 rotor and cartridge guide. I have rebarreled a few pre-1960 99Fs from 308 to 358 using factory barrels and have had a couple that would load/feed all 5 cartridges in the magazine and a couple that would only load/feed 3 cartridges in the magazine. A 'smith who knows what he/she is doing could rework a 308 magazine spool to 358, but there is a fair amount of hand work involved and it might be pricy.

Jeff

I have converted a number of 99s to various calibers but since Savage discontinued them parts are hard to find and most dealers have no clue what caliber the rotors they have are for..It can be a real headache and you may end up with a mantel piece! I don't think you gain squat with a .358 over a .308 and its certainly not worth the trouble..

I'll keep me eyes open for 358 carrier parts. What happens to accuracy with thinning out the barrel?? As for being necessary, probably not, but then it is a caliber I fell in love with. Even if I have to pay a few bucks for extra work, at least I will have a classic rifle in the caliber I want. I'm sure it will beat what they are asking on GB, or Auction arms. Could you guys pm me with your contact stuff, so I can keep you on my list. I may never call, but I just might get lucky. Rachel

You could just have the rifle rebarreled, too. You could upsize the barrel to keep the same wall thickness as the .308, and not change the balance. I would think that the .308 spool would be the same as the .243 and .358, as it's al the same case, but I'll defer to people with more experience in such matters. Of course, as 260Remguy said, if you get a C model, it doesn't really matter. Let us know how you make out.

How far can I go back to find a rifle that will handle the .358 pressures? I know the .308 line would be fine, but how about a 300 Savage.

IIRC, the internals were changes around serial # 900,000 to accommodate the longer 308 family of cartridges.

Sunshinegirl,
I too contemplated this conversion several years ago. I had a pristine Model 99 in .308 with a tang mounted safety. For several reasons, including problems having the barrel rebored, I abandoned the project and sold the gun. I believe I still have a brand new .358 magazine rotor. I will see if I can find it tonight when I go home. If you are interested, please email me and I will also tell you my tale of woe regarding my rebarreling experience. Good luck with your project.

Try contacting this gentleman. I think he does 99s. I'm at work, and the site is blocked here.
www.benchrest.com/hammonds