Hello I am new here and would like to know if anyone has necked the 308 Win up to 45 cal. I have been reloading forover 45 years and now collect DA Colts predominatly New services. I am interested in making a light sporter rifle to shoot 45 cal cast lead bullets as I also mould my own bullets. Not looking to creat a monster just a fun gun to shoot and possibly a lite brush gun for deer, bear size game. but I might try it on prarie dogs if they don't charge when wounded. Any insight into this or comments are most welcome and appreciated. Thank you olddudeone

Welcome to the forum olddude. Rules are simple, be nice and join in.

You might do a search here on the forum, this subject has been discussed in great detail with the pro's and cons argued a bunch.

You might want to think about a cartridge such as the 45/70 or the one below to give you something to headspace on. The 308/45 has been done, but for a bolt gun I'd sure recommend something with better head spacing characteristics.

http://www.stevespages.com/jpg/cd458x2.jpg

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Bob from Idaho

The case is not fat enough to haed space necked to 45. An Improved design could be pushed to .416 and even that is pushing it to the extreme...

Thank you Steve I am familure with the 458 American. But what I was thinking of was using a .451 sized cast bullet and a very small sholder on a blown out case for head space but I might be over my head , That is why I thought I would ask. was planning on using cast 45 pistol bullets. olddudeone

A friend of mine did something similar many years ago, but ended up scrapping the idea and using the 45 Win Mag.

If you go ahead with it, .30-06 cylindrical brass is easier to cut down than .308 is to neck up.

If you want a "small shoulder for headspacing" you could look at something like a 45-284 but, the case capacity may be to great for your intended purpose....

A

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By HIS stripes, we are healed...

Here is a nice .45 Colt single shot.
http://www.gunbroker.com/Auction/Vie...?Item=84834013

Assassin,
Do you know of someone who already has a reamer and dies for a 45-284? I've been looking to do one just for fun and would rather just rent the reamer instead of buying one. I've tried Clymer & Pacific..

I'm not sure how this can be done? Base of a 308Win is 0.473", a 451" projectile, add 0.010" each side for neck wall thickness (you'll be turning necks!) and your at 0.471" ... so no case taper at all where 0.005" per inch is considered absolute minimum for reliable feed/extraction in a bolt action!? Largest expansion of the 308Win case is a 0.429" projectile (eg ... 44AutoMag and 44/08) and these dont headspace on any shoulder as there isn't any, relying on a correctly trimmed case neck to headspace on.
Likewise the 284 case is really not suitable past 0.416" and those wildcats (eg 416-284McPherson) have "improved" shoulders over factory spec to make them wider. Any shoulder less than 0.025" (0.0125" each side) is asking for headspacing trouble, particularly if your a "sloppy" reloader when setting up dies etc...
They'd be an absolute bugger to open, but the WSSM case might be suitable.
Cheers...
Con

For doing a 45-284 chambering, cut the main body and neck with a regular 284 Winchester reamer, then a .45 caliber neck reamer and then cut the throat to the length you want with a .45 caliber pistol throating reamer...

Since you are going to be "renting" the reamers, make sure that the "base diameter" for the 284 Winchester does not exceed .499 cause if you go much above this, within just a few firings, your primer pockets will get too loose to hold a primer securely...

For dies, use Redding Bushing dies with the appropriate neck bushing and you can use a Hornady 45 caliber Universal bullet seater for seating....

A

__________________
By HIS stripes, we are healed...

Isn't there already a rimless 45 cartridge? http://en.wikipedia.org/wiki/.458_SOCOM

Assassin,
Looking at 284Win case drawings ... shoulder is 0.478". Take a 0.452" projectile, add 0.020" in neck thickness (0.010 each side) ... your at 0.472" and trying to headspace with a shoulder of 0.003" per side and on a rebated case ... a 0.458" projectile wont work. Seriously doubt it will work with a 0.452" projectile either. The McPherson 284 wildcats had their shoulders blown out to 0.486" and they stopped at 0.416" projectiles which gave 0.020" shoulder per side. Minimal shoulder to headspace is achieved with the 10.75x68 at 0.0125" per side.
Cheers...
Con

If you don't have anything against using 284 Win. brass, it would work just fine. Personally, I have been thinking about the 7.62X39 opened up to 40 caliber and shortening the case to 33 or 34 mm to give me 41 Magnum perfomance in a semi-auto carbine.

its near impossible to get to 45 but 44 works fine. I am working on an auto loader with 30-06 cases cut back and necked to take 44's

Hello.

Just to be persistant - if the .308 / 30-36 case were shortened to work through an ar-15 action, would there then be enough meat at the somewhat new wider shoulder to accept a .458 caliber bullet?

Also, pushing the envelope a bit - has any fed .308 Barnes, or similar cartridges, through an ar-15? Does the .308 case function in an unmodified ar-15 (STANAG) magazine?

Regardless of similar and or equivilant cartridges, I am looking at the prospect of using one case that functions in unmodified m-16 mags as the parent for several cartridges with a .473 rim.

I am looking at .458?, .375, .308, 6.5 (.264), and .223.

I am already looking at the .458 SOCOM as it works through the m-16 magazine and has the .473 rim.

Thanks.

I don’t know whether it will work or not.

With the 450 Bushmaster available I don’t believe there is a need for all of this work!
Here is a drawing courtesy of Greg Mushial’s cartridge designer. This case would require inside reaming and a bit of work to ensure headspace was maintained.

With only a rough 45.0 grains of water for case capacity the 450 Bushmaster looks like a viable competitor.

Attached Thumbnails

   

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slim

1. No, that is why the 458 SOCOM uses larger 50AE as the "parent" brass....it has a larger base diameter

2.yes, quite a few different ones that are similar but designed to work within AR15 pressure/ bolt thrust limitations.....if you use the 6.8 magazine a more can be added to the list.

3. you have 1 choice and that is the .458 SOCOM. That is what Teppo Jutsu designed it for, and why Marty went with the .458 in his design. if you start necking it down, the internal ballistics take it out of the safety window for the AR15 system. he is a very nice guy to talk to and you can find him at 458socomforums.com or the "ar variants" section at AR15.com or check out his company website at TeppoJutsu.com.

outside of your requirements of the .473 boltface and unmodified USGI mags there are a bunch of other possabilites......Olympic arms makes a bolt face and mags for the WSSM case, remington has the 30 RAR, Bushmaster has the .450 Bushmaster, and lots of places make .420 boltface and 6.8 spc mags.

advntrjnky

ETA: what you keep describing is the .45 win mag pistol cartridge....IIRC there have been a couple AR15 conversions done to it by Tromix.

Take a look at the 401 Win. cartridge, that's pretty much what your talking about. In the "SKS Accuracy!!!!!" thread in the ex-military rife section that very idea is discussed for an SKS conversion. HD1