300 Savage or 308Win in AR-15 Barrel?

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1stmarine

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Have you ever seen an AR15 barreled for the 300 Savage or the 308Win?
I know what you are thinking, why, how?
I know this is not normal but I just want to know. There is actually a simple solution to feeding from the AR-15 lower for certain rounds.
Thanks.
 
I can't imagine no one would have done it yet if it were all that simple.

As far as the barrel itself goes, I'll bet you could get one of the barrel companies to ream you a .308 or .300 Savage chamber pretty easily, as long as you were cool with throwing a little extra cash at 'em. or maybe they won't need any extra money, it's just a reaming job after all, and they won't care how successful your project is or isn't.

Sounds cool though, does it involve a side-feeding magazine?
 
Yep. I am working on a 5 and another 10 rounder.
Plenty for hunting at considerable range. I think it is easier to modify the mags than it is to come up with a new good round that fits in the old house.
For the 5.56 offspring I already built a series of VLD magazines. I have to modify the bolt stop. I am very happy with the 6x45 performance in the VLD feeder. Same setup is used by the AI folks.
I will keep asking to see if I could boot this. I am looking into a 18" big momma AR-15.
Cheers.
 
oh boy!!! . I am planning to sending the bullets by fax then.

Again...
Bore 308. Chamber 300 savage or 308win.
Cut to fit AR-15. Bolt face @ 0.47 and matching extension.

Please stay focused on the subject.
Thanks.
 
hardluk1,
That is a good point. It is an awesome offering and it has been considered.
These are my thoughts.....
A) It is proprietary and there are no reamers so I cannot have a barrel with specific characteristics.
B) I have truck load 308 brass that I can already use for reloading.
C) The Savage has the potential to launch a 160gr bullet at 2650fps. I like my trajectories to stay as close as possible to the desirable 2700fps with the most efficient bullets. The 30RAR cannot do that.
D) It is more fun, maybe? ;-)
 
It seems to me cutting a .223 bolt face to fit a .308 case would seriously compromise the safety of the bolt lugs.

I'm not even sure there is enough bolt carrier travel to be able to eject a loaded .308 round if you want to unload the rifle without shooting it?

That is why the AR-10 bolt and action is bigger.

There are several .30 cal cartridges that will fit an AR-15 action & magazine already out there with rebated rims to fit a .223 bolt face & extractor.

In all, I think it is a very bad idea.

rc
 
Even the 30RAR uses a larger bolt to accomodate the increased bolt head size. Same with the WSSM ARs and the 300 OSSM. Totally different bolts, carriers and uppers.

The OSSM will do what you want, and more.
 
oh boy!!! . I am planning to sending the bullets by fax then.

Again...
Bore 308. Chamber 300 savage or 308win.
Cut to fit AR-15. Bolt face @ 0.47 and matching extension.

Please stay focused on the subject.
Thanks.

OK then quit dodging the question and tell us how you intend to get a magwell that's maxed out in terms of lenght as exampled on the right (30herrett) to feed either of the two cartridges on the LEFT (308 and 300sav)

If you expect us to take you seriously you're gonna have to tell us how you intend to get around this obstacle. Because I assure you, you're not the first nor the last to inquire about 308 ar15's. Which in most cases is a complete newbie asking.

a6cd09e1-b2be-8ac0.jpg

Even with a plus sized bbl extension and bolt face both 30rar and 450 bushmaster (.473") case heads are held to much lower pressures than 308 in difference to the weaker bolt.

To do a 308 you'll need a wssm sized reciever and bbl extension. IE ar10 sized.

posted via tapatalk using android.
 
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Pacific tool makes reamers for the 30 remington ar cartidge. 147 bucks. The 30 rem ar bolt face is a couple hundreds larger so it could be done.

Theres no way to stuff that 300 savage round haveing to use a .223 mag to controle lenght. No matter what ar15 based rifle you pick your stuck

with a 2.26 OAL. The savage is 2.60 oal. Be very hard to push a 160gr to 2700fps with 308/300sav shortend brass down to around 1.53" and there is

data for the 308x1.50 barnes out there to look at.. Good health and life insurance ?? Wildcat cartidge time. Good luck
 
Hi guys. Nice points. Please see my comments below...

helotaxi,
The 300 OSSM is proprietary, expensive and reports show not that much accurate. It is clearly overbored for this platform. Also the WSSM bolts are not the strongest of all.

rcmodel,
It seems to me cutting a .223 bolt face to fit a .308 case would seriously compromise the safety of the bolt lugs.
No need to cut anything. This is the same used in the 6BR and 7BR bolts that are already in circulation. The extensions are very strong.

I'm not even sure there is enough bolt carrier travel to be able to eject a loaded .308 round if you want to unload the rifle without shooting it?

Yes there is enough room. The round is not larger than the magazine overall length. And the travel goes well past that otherwise it would never engage the bolt retain. The trick is how to squeeze the round in there. I am working on this.

That is why the AR-10 bolt and action is bigger.
It makes sense that everything is beefed up for all sort for 308 loads and uses but even a mild load is very reasonable. In the end the RAR and specially the WSSM deal with more powerful loads (ie: WSSM) with bigger bolt face, bigger section and weaker bolts than the 308/BR bolt face.

There are several .30 cal cartridges that will fit an AR-15 action & magazine already out there with rebated rims to fit a .223 bolt face & extractor.

In all, I think it is a very bad idea.

The AR-15 was created to fit the .223 round and not the other way around. We love the AR-15 calibers because we love the ARs but it is hard to find one round that is really popular in the bolt department, with the obvious exceptions of the .223 and 7.62x39 classic, in big part due to its military background.

My thought is to work with a popular round. In the end I will have to modify the loading mechanism once vs special/costly rounds that I have to potentially prepare hundred of times.

Thanks.
 
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R.W.Dale,
Please see my comments below...

OK then quit dodging the question and tell us how you intend to get a magwell that's maxed out in terms of lenght as exampled on the right (30herrett) to feed either of the two cartridges on the LEFT (308 and 300sav)
The 300 savage and 308 win will fit int he magwell with a good assortment of bullets. not all the bullets.

If you expect us to take you seriously you're gonna have to tell us how you intend to get around this obstacle. Because I assure you, you're not the first nor the last to inquire about 308 ar15's. Which in most cases is a complete newbie asking.
I understand your confusion. I never said this is already working but I think I am very close to make it work. My intention is to keep this a positive dialog and at the moment simply ask for feedback. If I thought it was not possible I would not be trying this. I have many wildcats in the AR15 so I am familiar with the limitations.

Even with a plus sized bbl extension and bolt face both 30rar and 450 bushmaster (.473") case heads are held to much lower pressures than 308 in difference to the weaker bolt.
Negative, for example .243 WSSM puts 65,000 psi with a wider section (less meat on the barrel around the chamber) and a weaker bolt compare to the new 6BR bolts in circulation.

To do a 308 you'll need a wssm sized reciever and bbl extension. IE ar10 sized.

Negative, the WSSM bolt and extension is yet another reason not to go that route. Some of those push the AR15 way too far. The new designs used in the 6 and 7BR more appropriate I think and based on section alone back thrust should not be a concern.
 
You do understand that wssm uppers DO NOT use the same diameter bbl shank and extension than the ar15

gund.jpg


Another point you're missing is that even if you get 308/300 to feed using low BC short bullets all you've done is create a handload only cartridge. If it wont chamber and shoot commercial 308 then its not chambered for 308 then is it?

posted via tapatalk using android.
 
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I know that.

But it doesn't change that the 6mm BR is not loaded to as high a pressure as the .308 when comparing whittling out a .223 bolt face to fit one ot the other.

Lets just say that the 6mmBR is a lower pressure round then the .308 and leave it at that.

rc
 
R.W.Dale,
Yes Thanks. But if you look at the section you end up with less difference (meat) around the chamber. But this brings an interesting point. Would it be better to put a wider and stiffer section even if it is not 100% needed.

rcmodel,
Lets not forget the Savage that I put in the post. I am looking at this as a more attractive option for several reasons. SAAMI pressure 47K psi but CIP std. pressure 53K psi. Since the savage is the parent case for the 308 I can produce many "free brass" using the 308. I have thousands of x1 fired. The 308win SAAMI is is 62K Psi not 65K Psi. Look it up if you want. But this is not even the point. Both the savage and the 308 can be pushed further safely. Also any BR shooter can confirm the 6BR will do 57 PSI all day w/o any signs of stress.
But, for my purpose in this platform I am perfectly ok with the average 300 savage load. I do not need to push it any further and get into the red. In the end this is not intended to beat any record. Actually, once the feeding issue is overcome, I look at it as an easier option round.

Even Stoner faced his own challenges at first. They though the AR15 was a plastic toy. The Army didn't want it. But he was a tenacious man of science and persevered.

Thanks guys. I know this looks like an old tale but if it was easy I wouldn't be asking around and it would have been done. I just wanted to take a totally different route for the next upper.


ps.. and I almost always reload so this is not an issue for me. Thanks for pointing that out though.
 
I am looking at this one from the guys from AR performance in Colorado...
They seem to have very good stuff over there. The 308 bolt face is the one on the right. Very strong reports say...

boltcomp.jpg
 
Do your self a simple measurement of the metal ar mags And you will find that even if you can make the full lenght 300 savage function in the upper it will NOT load in ar15mag with full out side dimintion of 2.45" lenght front to rear. I don't believe your even a deep set lenght 125gr word intrud on case capasity .much less a 160+ gr bullet so reguardless of what you contrive with the upper issue the lower won't work.
 
Hi hardluk1,
it is all measured and figured out. Actually I just came from my workshop and I have an almost working prototype. MEasure the magwell and see for yourself if a nice savage round is smaller or larger than that.
We will use the hammer to stuff it in there if needed. ...I am joking. LOL!

Resolving things.... just like at work but more fun. :)
 
Well you will be compressing and shortning the cartirdge is its not the mag well you have todeal with but the mag it self. Just be sure you have good insurance. When AR blow they tend to do it very bug.
 
hardluk1,
Good points. Don't worry whatever we do, safety first.
The magazine is modified so the cartrige can be loaded at length.
I cannot use the longest long range/VLD bullets but this is not the purpose of the upper anyway.
Thanks.
 
But wasn't useing even the 160gr bullets a prime need for you. It will have to be deep set and that defeats the purpose of the 300 savage stock brass With a inside lower mag opening of from the recess to recess being 2,606 and room haveing to be made for the mag it self, wiggle room and then a cartridge you will have to run short cartridges and stock factory ammo will not run. Also getting over 2700fps out of 150gr bullets is pushing a 300 savage . If nothing factory in ammo will work it is another wildcat with altered brass and that has been done ever which way from sunday. But good luck with your guys project. Rather have 6.5 or 270 version anyhow, better BC and down range performance
 
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