Also, I have a barrel assembly with a handguard cap that's obviously made for triangular handguards. I'll order a new one, but was wondering if I'd have to replace the slip ring as well. Or are the old ones compatible with new symetrical handguards?

Well, the newer  Handguards will be compatible no problem... they are designed to do that and I had a SP1 that i swapped to the round HG's. Got a pic of the stock? I could tell ya by looking at it...

Nathan

Haven't got a camera at the moment.

Unscrew the top screw on the rear of the buttstock.  Slide the stock off of the tube.  If there is a spacer on the end of the tube (or sitting in the stoock still) it's an A2.  The A2 is 5/8th longer...and requires this spacer.    

Another thing, look at the length of the screw.  If it's about an inch long, it's an A1.  If it's closer to 2 inches long, it's an A2.  The screw will be different on each, because they have to account for the spacer.  

And be careful, there's a detent spring thing that may fly when you slide the slock off, so go slowly.

Quoted: Unscrew the top screw on the rear of the buttstock.  Slide the stock off of the tube.  If there is a spacer on the end of the tube (or sitting in the stoock still) it's an A2.  The A2 is 5/8th longer...and requires this spacer.     Another thing, look at the length of the screw.  If it's about an inch long, it's an A1.  If it's closer to 2 inches long, it's an A2.  The screw will be different on each, because they have to account for the spacer.   And be careful, there's a detent spring thing that may fly when you slide the slock off, so go slowly.

There's no screw and no tube. That's why I'm asking, so I can order them.

Quoted: Quoted: Unscrew the top screw on the rear of the buttstock.  Slide the stock off of the tube.  If there is a spacer on the end of the tube (or sitting in the stoock still) it's an A2.  The A2 is 5/8th longer...and requires this spacer.     Another thing, look at the length of the screw.  If it's about an inch long, it's an A1.  If it's closer to 2 inches long, it's an A2.  The screw will be different on each, because they have to account for the spacer.   And be careful, there's a detent spring thing that may fly when you slide the slock off, so go slowly. There's no screw and no tube. That's why I'm asking, so I can order them.

Take a ruler and measure along the top.  
NOT including the butt-plate, my A1 measures 9.5".  And A2 would be 5/8ths longer than this.
Hope this helps.

Quoted: Take a ruler and measure along the top.   NOT including the butt-plate, my A1 measures 9.5".  And A2 would be 5/8ths longer than this. Hope this helps.

10 1/8. Thankyou for taking the time to do that.

Quoted: Also, I have a barrel assembly with a handguard cap that's obviously made for triangular handguards. I'll order a new one,

No need - A2 handguards work with either handgaurd cap.

but was wondering if I'd have to replace the slip ring as well. Or are the old ones compatible with new symetrical handguards?

Nope.  There is no need to replace it.

Quoted: There's no screw and no tube. That's why I'm asking, so I can order them.

Easiest way to tell is to look where the sling swivel slot is in relation to the buttplate.

If it's near the buttplate then it's an A2 stock, if it's at leat an inch to an inch and a half then it's an A1 stock.

If the stock is completely hollow inside (no foam surrounding the area for a cleaning kit) then the stock is an A1 length C1 stock from Cav Arms.

This is an A2 stock, not the sling swivel is about a finger's width from the edge of the stock before the buttplate, the A1 stock is at least twice that distance away: