anyone here done 300 wsm in an ar-10

[mel80]

any major issues or complaints?
ive been looking for a new project and i think ive found it.

what im thinking is a 26" barrel with 1-9T +2 gas
that i could swap out with my 6.5 creed barrel since i dont shoot the creedmoor anyways
and id have to enlage the ejection port on my upper along with a new bolt , which ive already priced up , so id be looking at around 650-750$ for a possibly fun long range target build

also on the plus side projectiles and brass is plentiful

and a good selection of high bc bullets ranging from 170-230g

 

[stagpanther]

Right off the top of my head A magnum bolt face is going to be problematic in an AR--although it can be done with something like KAK's bolt. Then there is the issue of reliable feed from the magazine, which can end up being a big issue with an AR when "going off the reservation" from standard cartridges. I thought about it a long time ago and decided against it when someone pointed out for the cost of the brass I'd end up spending a lot of time on my hands and knees scavenging in the leaves for ejected cases. I bought a 270 WSM in a model 70 when I couldn't find a 270 wby mag chambered rifle, it's turned out to be rather "meh" IMO and I should have held out for the Weatherby IMO. You might want to take a look at a PRC if you're willing to pay for the upper that can take it. Or perhaps a SAUM which seems to be doing well in match shooting.

 

[mel80]

Right off the top of my head A magnum bolt face is going to be problematic in an AR--although it can be done with something like KAK's bolt. Then there is the issue of reliable feed from the magazine, which can end up being a big issue with an AR when "going off the reservation" from standard cartridges. I thought about it a long time ago and decided against it when someone pointed out for the cost of the brass I'd end up spending a lot of time on my hands and knees scavenging in the leaves for ejected cases. I bought a 270 WSM in a model 70 when I couldn't find a 270 wby mag chambered rifle, it's turned out to be rather "meh" IMO and I should have held out for the Weatherby IMO. You might want to take a look at a PRC if you're willing to pay for the upper that can take it. Or perhaps a SAUM which seems to be doing well in match shooting.

yeah i was planning on grabbing a kak bolt if i did go ahead and build one.
i hate my creedmoor build so i wa slooking for something new to play with that i could pretty easily do with my ar-10 build and not be to exspensive . if i did anything larger it would just end up being a bolt gun build and would be something more along the lines of 338

i did find this video of a kak 24inch wsm upper
https://www.youtube.com/watch?v=sAo3yeJLO88

 

[stagpanther]

yeah i was planning on grabbing a kak bolt if i did go ahead and build one.
i hate my creedmoor build so i wa slooking for something new to play with that i could pretty easily do with my ar-10 build and not be to exspensive . if i did anything larger it would just end up being a bolt gun build and would be something more along the lines of 338

In addition to the cartridge feed ergonomics there's also the issues of gas balancing and the bolt to extension lock-up, not always an "automatic ease of .308" thing when trying out non-standard cartridges. Can't remember if it's Noreen or some other outfit--but there is somebody out there that offers receiver sets that are engineered to take cartridges that are longer than the standard 2.8". If I were venturing away from the standard bolt face size .473 I'd probably look into an outfit that could make me a matched-set barrel and bolt, taking care (presumably) of the headspace and bolt/extension lugs configuration for me. "Cheap" and "rarely encountered chambering" almost never go hand-in-hand when conjuring up a new build.

I don't mean this in a condescending way (your results with both the grendel and ARC far exceed anything I've been able to do with either of those)--when I read between the lines that you hate your creedmoor--having built 4 creedmoor AR's myself--I'm wondering if you have had issues getting it to function reliably and accurately. They are tricky gas guns to balance right--other rarely chambered cartridges are likely to be the same or even more challenging.

 

[jmr40]

I don't know if this is relevant or not. But the WSM family of cartridges are fatter than the standard belted magnum cartridges. This could complicate things even further with the bolt face and getting them to feed from the magazine.

 

[HiBC]

For a time, it was possible to get an upper for an Armalite AR-10 from Armalite in Remington's .300 RSAUM. Its like the WSM but a bit shorter. AFAIK, its discontinued/unavailable.(The upper)

Brother has one. His works and he's happy with it. There was a little "fiddling" to get everything just right.
He has a .308 upper that gets used most often .

I can't say I "know" anything much about it,but I assume Armalite had their reasons to choose the RSAUM over the WSM. FWIW.

 

[stagpanther]

I can't say I "know" anything much about it,but I assume Armalite had their reasons to choose the RSAUM over the WSM. FWIW.

Case web stronger I think.

 

[mel80]

Case web stronger I think.

this is the reason

norren doesnt seem to just sell there reciver sets , just std ar15 and and ar10 stuff.
as far as my cm build i just dont like it for the simple fact i can do anything it can with my grendel. i always end up grabing on of my grendel builds over the creed builds when going out ive shot either of my cm's literally once in the last 2 years

i did find a place that will do rsuam barrels as well so thats also an option
still looking around for something that might also keep me entertained for a bit as a project , ive found a few that i may like just gota do a ton more reading on some of them

 

[stagpanther]

norren doesnt seem to just sell there reciver sets

I know somebody does--I looked into making "oversize" AR 10 a while ago and did eventually find someone. Sorry I can't remember who it was but if you search enough I think you'll find them (unless they gave up and don't offer them anymore).

 

[mel80]

holy hell 300 rsaum brass is exspensive lol 68 per 25 from nosler

 

[stagpanther]

I paid more than that for 6.5 PRC cases recently. Saums and PRCs are in demand. I did spend some time looking around for a set of receivers beyond 2.8" and couldn't find them, I think Olympic once offered them (before they went out of business) for their own version of WSSM. I'd be interested to see if someone comes out with a 6.8 western AR--which then would likely be necked up and down in other calibers.

 

[mel80]

i actually found some for 66 per 50 so its about on par with the wsm stuff

 

[stagpanther]

I'm interested in knowing who will actually make the barrel for you. McGowan used to be "indulgent" in the barrels they would make for me--but not anymore. I think the way to go would be a fast twist adaptation of a 6.8 western which also allows the use of the newer, bigger high BC bullets--should be able to make that work if you can get your AR 10 set-up to work with 2.95 COL, which might be possible with some "adventurous" machining. I built a 284 win AR which I run COL's out to about 2.905. Even with that the magazines are going to be a pain. It appears the big boys like noreen and APF are only interested in keeping their receivers proprietary forcing you to drop BIG bucks on assembled rifles.

 

[mel80]

mcgowen , deadshot and a few other places will do them , mcgowen would obviously be my goto for the barrel though

 

[stagpanther]

mcgowen , deadshot and a few other places will do them , mcgowen would obviously be my goto for the barrel though

Very cool, look forward to seeing how your project turns out. McGowen made my 284 win AR barrel for me. The magazine stacking cartridges is a headache--but other than that it shoots great.

 

[HiBC]

The fat RSAUM case is a "1 1/2 stack" rather than a double stack mag.

There is some form of slick adhesive backed plastic shim that my bro stuck to the inside surface of the mag that seems to have overcome any issues.

It might be a while,but next time I see him I'll ask about details.

 

[mel80]

2 options im looking at currently are the 7mm saum and the 300 rsaum both have adavnatages and disadvantages , witht he goal being target shooting at the longest possible ranges the 300 may win out

 

[stagpanther]

Personally, the concept of "squeezing" a magnum cartridge into a standard short action AR receiver is a losing proposition from the get-go IMO for the simple reason between the datum where the barrel extension ends and magazine well depth (clearance front to back) will never allow enough cartridge length to truly exploit maximum efficient use of modern very high BC bullets. I've spent a lot of time dickering with them and trying, it becomes a musical chairs of tuning and grinding. Sometimes I wonder if the "fatty" magnums are chasing the dream of a "supersized" reincarnation of 6 ppc. Although it means paying a $1,000 or more premium over what you could do yourself, I'd look at biting the bullet and buying the noreen 30-06 carbine at around 2K to get my foot in the door with the receivers and then have the option to reconfigure to other long action cartridges. Now a 280 AI AR--that gets me excited. Or maybe find someone to go into business with making them yourself, though others have tried and so far doesn't look like anyone has made much of a market out of it at their high prices.

 

[mel80]

Personally, the concept of "squeezing" a magnum cartridge into a standard short action AR receiver is a losing proposition from the get-go IMO for the simple reason between the datum where the barrel extension ends and magazine well depth (clearance front to back) will never allow enough cartridge length to truly exploit maximum efficient use of modern very high BC bullets. I've spent a lot of time dickering with them and trying, it becomes a musical chairs of tuning and grinding. Sometimes I wonder if the "fatty" magnums are chasing the dream of a "supersized" reincarnation of 6 ppc. Although it means paying a $1,000 or more premium over what you could do yourself, I'd look at biting the bullet and buying the noreen 30-06 carbine at around 2K to get my foot in the door with the receivers and then have the option to reconfigure to other long action cartridges. Now a 280 AI AR--that gets me excited. Or maybe find someone to go into business with making them yourself, though others have tried and so far doesn't look like anyone has made much of a market out of it at their high prices.

i talked to afew ppl that have them they all say the same thing there a bit tricky to get to run right but they love them , looks like biggest issue is they are supper picky on magazines , but other then that everyone seems to love them, i dont mind having to play with it hell i had to playw ith my long grendel a bit to get it running great so wont be nothing new. though i still havent made a decission on which way im going to go

 

[stagpanther]

i talked to afew ppl that have them they all say the same thing there a bit tricky to get to run right but they love them , looks like biggest issue is they are supper picky on magazines , but other then that everyone seems to love them, i dont mind having to play with it hell i had to playw ith my long grendel a bit to get it running great so wont be nothing new. though i still havent made a decission on which way im going to go

Understood, I just see some inherent limitations in using short actions in regards to what you can realistically expect in long distance performance without going long with bullet seating; just like the grendel and creedmoor (which actually were purpose-designed for bullets to be seated long) without encroaching on case capacity. With higher BC bullets in the AR you will likely hit the wall faster between seating the higher BC bullets longer and seating them deeper in the case, possibly with the base of ogive into the neck, in order to get them to adequately feed and chamber. Getting them to that point after a violent cycling in good style is hard to do in itself. But I don't have any of those chambering in an AR, and especially since you have friends that have already done it that's a big help. I look forward to being shown wrong by you.