.300 Savage re-chamber to .308 Win

TomL

New member
Hello all, I wonder is this is a easy upgrade for a Model 99 as in just reaming the chamber for the longer neck/case of the .308 or do we run into magazine length issues and/or chamber pressures? There seems to be a few .308 M99's around but had my eye on a nice 99 in .300 but would prefer the .308 chambering. Thanks. Tom
 
Not much difference in the case other than neck length.
If OAL in within limits it should work in the spool magazine.

Standard 150 gr hunting loads for the .308 are not high pressure loads. Heavy bullet and long range match loads, along with some 7.62 NATO long range MG or sniper loads may be too hot for the 99.

The savage lever action was at one time available in .308, though this version used a detachable magazine instead of the more common spool type rotary mag.

PS
I'd strongly advise against rebarreling or rechambering a .300 Savage model 99 if it has a good bore and chamber as is. The unaltered rifle is a collectors item these days.
 
Last edited:
I wouldn't do it. The rotary magazine 99s are troublesome to switch from 300 Sav to 308. The magazine rotor cutouts are the same shape and size as the cartridges themselves, and some 99s are tighter than others. A 308 Winchester is about 1/8" lonfer than a 300 Savage cartridge, so there may be issues. In addition, the 300 Sav operates at 48,000 psi, the 308 Win operates at 60,000 psi. This is the reason Savage strengthened and lengtheded the Sav 99 receiver design in the mid 1950s when they started offering the rifle in 308.
 
The .308 maxium chamber pressure is 62 K PSI around 60 K CUP, but operating pressure for the 150 gr loads is around 48,000 CUP - 51,000 PSI.
I would not want to use the long range match ammo or extra heavy big game loads in a Model 99 but standard velocity 150 gr Deer loads should not be a problem.
 
Not a good idea as you will run into both length and pressure issues. Besides a nice 99 is a collector's item now and will be more so in the future. Keep it original.

If you want a 99 in 308, buy one that came that way from the factory.
 
.300 Savage re-chamber

Thanks for the replys. I kind of figure there was a good reason(s) but had to ask. I didn't know about the .308 box magazine(99F?)and the 99 in that chambering are quite generic/homely in appearance as compared to the 99 in .300. Not too appealing for my likes. It's not a collector piece I want, there are plenty of them still for sale, some ridiculously high priced of course. It will be a hog and deer killer to be precise and since the .308 round is more attainable than the .300 from what I read, that was my thinking regarding the re-chamber.

I do not have at hand my Hornady reloaders guides so cannot read and compare ballistics and bullet types so would one of you post some comparisons using 130-150 grain data of both .300 and .308. Thanks again. Tom L
 
Rainbow Demon, your info on .308 pressure's not all correct. Please refer to the following starting on page 13 for CUP and PSI data for the .308 Win as well as the .300 Savage paying close attention to the pressures for all bullet weights:

http://www.saami.org/specifications_and_information/publications/download/206.pdf

And regarding the Savage owner's objectives of wanting it chambered to .308 obviously outweighs his desire to have it be a collector item.
 
Last edited:
I've killed a lot of deer with a Savage 99 in 300 Savage caliber, I would think it would work equally well on hogs.
The 308 does have better ballistics and the ammo will most likely be less expensive, however if you use the 300 Savage I believe you will be pleased with it's performance.
In my opinion the handling ability of these old rifles is superb.

Best Regards
Bob Hunter
www.huntercustoms.com
 
Get some experience with the .300 Savage before you move to the .308

I have family members that have killed uncountable number of deer & other game with the .300 Savage in the 99. It is an excellent cartridge/gun combination & there is very little if anything to gain converting it to a .308. If you'll try it on deer & hogs I'm sure you'll realize that rather quickly. Use the money you save not converting to start reloading. Then your .300 will be suitable for everything up to caribou with the right load.

Looking in several loading books for 150gr bullets (best bet for deer & hogs):
.308 Win max velocity is 2700 to 2900 fps
.300 Savage max velocity is 2500 to 2700 fps​

Good Luck!

...bug
 
+ 1

The cost of conversion would be better spent on ammo and/or reloading. If you only shoot it a little bit for hunting and to check your sights, 100 rounds would be plenty, I suppose. But for a caliber that's not as common as it once was, perhaps having a reserve of 500 rounds with the ability to reload would guarantee a lifetime supply even if you shoot it quite a lot.
 
.300 Savage re-chamber

Hello, all posts make good points. I was a serious reloader many moons ago, still have all my equipment but just stopped due to life and its trappings. Maybe its time to pull the stuff out and take up the hobby again. I did some searches and the 150 gr psp .300 Savage is selling between 37-40 dollars a box of 20. 120 rounds might well last me years of hunting including a 3 round group to check sighting. To my thinking its doubtful I could get a re chamber done for the ammo cost and take into consideration the effect of what that would make the rifle into instead of what it was! Thanks all. TomL
 
Hey all, don't underestimate the killing power of that 300 Savage, my 1951 Model 99 has taken several Elk in Utah as well as countless Whitetails.
Not by my hand, but the previous owners, he used 150 grainers for deer and 180 grainers for Elk. Keep the shots reasonable and it will do it's job, and do it well.
A Model 99 can be had in 308, just have to look long & hard with lots of patience. Been reloading the 300 for years and got the best results with BLC-2 and Sierra
150 grn round nose bullets (1-7/8"@100) and H-335 with 165 grn Speer Grand Slam's (1-3/8"@100), don't know the velocity, but out to 250 yards or so this one is deadly! :cool:
 
Last edited:
Not worth the effort and money involved. If you see a .308 and it seems expensive, wait until you pay someone to change over a .300 Savage.
 
When Savage added 243, 308 ,and [7/08 ??] to the 99 they also changed the steel type/HT. they did that for a reason!!
Rechamber is not recommended !
 
I have been hearing that for years. What type of steel was being used opposed to what they went to later? Sounds like a rumor to me. Nobody ever knows what kind of steel is actually used. I have worked on quite a few 99's and the later models actually have more steel milled out of them. Facts if you have them. I am interested. I have a piece of a receiver some one was kind enough to donate to me, and I will eventually do some testing on it when I get time. I would not be afraid to barrel a 99 to .308 that was made in the early 40's.
 
I've used both, and can readily testify that no deer, shot with either the .308 or the .300Savage, ever knew the difference.

BTW - IIRC, the detachable-magazine version of the .308 chambered M99 was the 99-C.



.
 
I don't remember the source of the info.
There are many things that are changed that the consumer knows nothing about.They may be changed for any number of reasons.A few shots fired safely isn't the only test. Long term use may show up other problems.
 
Sav99takedown6mmBRa.jpg


This is a 1917 Sav 99 250 Sav take down that I drilled and tapped for scope.
I threaded and chambered a 6mmPPC shilen stainless select match take $50 take off barrel for SAV99 and 6mmBR.

I have been shooting it at ~ 80,000 psi with the same case head as the 308, but the 308 case head cannot go that high. The primer would fall out. The 6mmBR limit is a pierced primer. I use the toughest primer, the CCI 450 small rifle magnum primer. I run it just below the threshold of a pierced primer.

The brass stretches ~ .003".
The action locks up in the rear.
Different steel with different heat treat of alloy may have different yield strength, but they will all have the same modulus of elasticity. That means it does not matter what vintage Sav99, they will all stretch the brass the same amount.
 
I have a Savage 99 that was my Grand Fathers, my Fathers, now mine and will some day be my sons. I wouldn't change a thing on it, it is all original. It has taken deer and black bear. It is a family heirloom and very valued possession.
 
Back
Top