Any one here have a .243 WSSM in an AR upper?  Where would I find a barrel/bolt for such a caliber? Is Olympic Arms the only source for barrels? Does it take a standard upper receiver?

TIA

For the WSSM you should talk to Mike Milli. He has been building these uppers for the AR for some time now and can answer any questions that you might have.

Here is a link to his web page.

Mike Milli Custom Guns

+1 on going to Mike Milli for help.  Oly arms is the only maker of the bolts and barrels to my knowledge and Mike has a great reputation for making good uppers using their parts (and being very helpful).

The only other close thing I know of is http://www.accuracysystemsinc.com/ar15_conversion.php
who make something almost identical to a WSSM for the ar-15 platform.  

My Oly 243 WSSM works like a dream and is amazingly accurate.  My only recommended addition for it would be an adjustable gas block if you want to broaden your powder options for reloading.  

Also, I believe the ejection ports on wssm ar upper receivers are larger than those on standard ar-15s.

The only sources I know of are a Mike Milli upper or the whole rifle (K8 Magnum) from Olympic.  I have the K8 in 25 WSSM.  Very accurate, but also very heavy with the 24" barrel by the time you add a scope and riser blocks.  Mike can supply shorter fluted barrels if weight is an issue.

I believe the Accuracy System guns use their own catridges which have rebated rims to fit standard AR-15 bolts.  

height=8

Quoted: The only sources I know of are a Mike Milli upper or the whole rifle (K8 Magnum) from Olympic.  I have the K8 in 25 WSSM.  Very accurate, but also very heavy with the 24" barrel by the time you add a scope and riser blocks.  Mike can supply shorter fluted barrels if weight is an issue. I believe the Accuracy System guns use their own catridges which have rebated rims to fit standard AR-15 bolts.

I was thinking about getting one of those .25 WSSM uppers...what do you mean when you say VERY accurate...can you give some groups sizes 100/200/400yards?

The last time I shot a group with it the last 10 rounds I fired were all within a 3" circle at 300 yards.  I made some scope adjustments later in December but did not shoot a group, however  I can tell you the last round I fired hit within an inch of where it was supposed to at 300 yards.  I would say it is definitely a 3/4 MOA rifle and maybe better.  I am using all handloads w/ weighed powder charges - 40.0 grs 4895 - and 100 gr Sierra Matchkings.

What kind of velocity are you getting if you ran it through a chronograph?

I like the concept of the WSSM ctgs out of an AR. Having said that though, they do have some shortcomings. The mags are rinky-dink. Particularly with the 25 WSSM there really isn't enough room in the mag for even some factory loads, you have too seat the bullets deeper. I hear they are barrel-burners par excellence also. What it really needs is a dedicated mag instead of modified GI mags & the case needs to be shortened 100 thousandths or so. Winchester & Browning factory bolt guns are Chrome-lined in these calibers, even though the manufacturers don't mention it. They know. OLY's barrels aren't lined. They tried too do Chrome lining years ago & couldn't get it right. They peeled like crazy & they have avoided chrome-lining like the plauge ever since. M9

Quoted: I hear they are barrel-burners par excellence also.

Is the 25-06 a barrel burner?  I've never heard the 25-06 burning out barrels, and the 25wssm has the same ballistics as the 25-06.

Never chronographed the load (I might next time) but the Hodgdon site shows the following for 100gr Sierras and IMR4895:  39.0 grs->3,055 f/s, 42.5 grs->3,259 f/s, so I'm probably in there somewhere.  Working up to 42.5 grs where I will stop.

I have read at least once that some 25 WSSM factory ammo might be too long, but I have never used anything but reloads so I can't comment on that.

I don't think the 25 is much worse on barrels than the 25-06, but it could wear throats faster as it does run at a higher pressure.  Of course the 243 will be worse and the 223 worser (I know that's not a word but everyone knows what I mean).  Win/Browning does chrome line the 223's and 243's but not the 25.  That was one of the reasons I picked the 25 over the 243.  On the other hand a barrel change on an AR is easier and cheaper than on a bolt gun, so if you really like the 243 go for it.

All the nay-sayers talk about "barrel burners".  I have yet to have any of them come in with any accuracy issues, much less throat errosion.

I have cronographed the 120 grain factory loads out of a 22" barrel and got 2985-2987 FPS, with single digit standard deviation.  My hand-loaded 100 grain Nosler partitions are going out at about 3250, and my 87 grain spitzers at a little over 3400 fps.

5 shot groups in the .2's are not at all uncommon with either the .243 or the .25.

The magazine length is a limiting factor for some of the high-BC bullets, but everyone seems to be doing just fine with that constraint.  I have had customers mill away the top-front of the magazine in order to shoot bullets seated out further, but I have never found it necessary.

I am in the process of building a quick-twist 6.5 right now.  I have no idea what or how he's going to use it, but he's anxious to get it!

I have an Oly 243 WSSM with a 20" SUM barrel. Plenty accurate with me behind the wheel, always sub-MOA out thru 400 m with just about any load that I have played with so far. Barrel life...if you are looking for an AR to shoot a 3 gun match with or blast then of course this is not for you, if you want an AR platform with long range capability then the stainless Oly barrel or something from Mike will last as long as any other high performance round going this fast. My experience with Oly (contrary to what appears to be the popular opinion on this board) is they make an AR as good as any other quality maker out there. I have Bushy, Oly, DPMS, and my work gun is a Colt...can't tell a lick of difference in overall quality. Some have better triggers, better barrels etc but all shoot well and all go bang when I squeeze the trigger. I wanted a 25 WSSM but availability drove me to the 243, very happy with this and bullet selection in an AR mag is better. Mags are no problem, modified a second GI issue and it works perfectly. Just mic the mag that Oly sends and match it. The only issues I have had deal with the extremely robust brass that Winchester makes these rounds with. Getting a proper neck seal takes a few reloads or anneal the necks. My 243 seems to want to run and group at the absolute maximum pressure also.

Quoted: I am in the process of building a quick-twist 6.5 right now.  I have no idea what or how he's going to use it, but he's anxious to get it!

  I & several others tried to get you to build a quick twist 6.5 a couple of years ago. Back then you wouldn't touch it with a 10 foot pole, because OLY didn't make a 6.5 barrel & you refused to use anyone else's barrels for fear of offending OLY. Whats changed? I still think the case will have too be shortened to make a useful quick twist 6.5. The only reason for a quick twist 6.5 is long heavy bullets. They won't fit in the mag with a full length case. If you are using a full length case, it'll be a single shot. M9

PS Actually I'd like a shortened 25 WSSM with a 1 in 9" twist to use the Berger 115 VLD from the mag. A 257 is really a 6.5. 264 is more like 6.7. Have you ever fixed the problem with the mags malfunctioning when upward pressure is applied? Seems like it should be an easy fix, with a little welding.

Quoted: I like the concept of the WSSM ctgs out of an AR. Having said that though, they do have some shortcomings. The mags are rinky-dink. Particularly with the 25 WSSM there really isn't enough room in the mag for even some factory loads, you have too seat the bullets deeper. I hear they are barrel-burners par excellence also. What it really needs is a dedicated mag instead of modified GI mags & the case needs to be shortened 100 thousandths or so. Winchester & Browning factory bolt guns are Chrome-lined in these calibers, even though the manufacturers don't mention it. They know. OLY's barrels aren't lined. They tried too do Chrome lining years ago & couldn't get it right. They peeled like crazy & they have avoided chrome-lining like the plauge ever since. M9

A good while back Winchester addressed this barrel burning problem, especially for the 22 caliber short mag...saying it wasn't true.  They did say that all of them hace chrome linesd bores.

Quoted: A good while back Winchester addressed this barrel burning problem, especially for the 22 caliber short mag...saying it wasn't true.  They did say that all of them hace chrome linesd bores.

 I'd expect them to have a fairly good barrel life with a chrome-lined bore, but OLY barrels aren't chrome-lined. But then again a barrel is just something you have to fiqure on replacing in a hi-po ctg. I think the real answer is to shorten the case a little more for use in the AR. Its really a little too long too be optimum out of an AR mag & that would improve the barrel life also. The biggest hurdle to shortening it seems to be that the brass is too thick already. M9