I replaced my A2 stock with an A1 with no problem (removal of spacer and replacement of stock with A1).  It was still too long, so I replaced the A1 stock with a RRA entry stock & DPMS 1" spacer, giving me a perfect LOP.

I replaced everything that I needed to (put in the internal spacer, replaced recoil spring and buffer, replaced buffer tube) but I think that something might be wrong.  The AR SEEMS to be recoiling harder than it did previously.  As a matter of fact, I put about 80 rounds through it today and it seemed like it started recoiling harder somewhere in the middle of the 80 rounds.  I thought that it might be my imagination but I don't really think that it is.  Any suggestions?

The carbine buffer tube and recoil spring is shorter.  The carbine buffer is 2.9oz compared to the fixed stock buffer with 5.3oz.  The lighter weight and spring would result in faster cycling.

I don't know what would make it change as you where shooting.

More info to make sure:

This is a postban Bushmaster shorty with 16" barrel and no brake.

New stock is a Rock River Entry stock (fixed stock...just shorter), spacer is 1" DPMS.

So the buffer that I put in is lighter than the old one?  I hadn't paid that much attention to them other than to keep them separate.

Can I replace the carbine buffer with the heavier buffer and lighten the recoil again if this is the problem?

Tell us more about this 1" DPMS "internal spacer".

Got a pic? Where does it fit in the gun?


[acronym]

OK, I've thought about this a bit longer now.

Is the spacer of the type that fits between the rear of the lower and the front of the buttstock and simply increases the length of pull? Is that what you meant by "internal"? It's kind of "internal" to the stock? I was imagining a part that was "internal" as in "inside the lower receiver extension."

Make sure that the extra long screw that came with the spacer isn't sticking into the LRE. Inspect the rear of the buffer for impacts.

Does your bolt come fully to the rear?

OK...here goes:

1" spacer is to increase LOP.  There is a 1" spacer that fits between the buttstock and the lower and there is an internal spacer that fits on the back of the recoil buffer.  These items, along with a couple of screws, come with in the DPMS spacer package.

The RRA stock came with stock, recoil spring, shorter buffer, and short buffer tube.

Everything from both of these packages was used with the exception of one screw which is a long one and is intended for use with an A2 stock if you use the spacer to make the LOP even longer.

SO...

Tweak, there are BOTH internal and external spacers.  The extra long screw is for use with the A2 stock.  The long screw is being used.  The rear of the buffer is clean and has not impacted the screw.  The bolt comes all the way to the rear, as far as I can tell.  There are no problems with the bolt locking back on the last round or short-stroking.

The buffer buffer? There is an extension on the back of your buffer? That doesn't sound right, am I tracking?

Edited to add I'm headed over to DPMS Inc's page now to see if I can find a pic of this kit.

Sorry...my mistake.  What I meant to say is that there is a spacer that fits on the back of the buffer TUBE.  Same as the buffer that goes on the back of the buffer tube when using an A2 stock except that it is 1" rather than 5/8".

Is this the kit?
[img]http://www.dpmsinc.com/products/BP-14.jpg[/img]

You do have the carbine buffer and carbine spring installed right?

This buffer
[img]http://www.biggerhammer.net/ar15/buffers/6001bfr1.jpg[/img]
not this one
[img]http://www.biggerhammer.net/ar15/buffers/6600bfr1.jpg[/img]
and a spring that is between 10 1/16"-11 1/4" long?

I apologize for what must seem like stupid questions but we have to eliminate the obvious things first. You said the change took place AFTER changing the stock so most likely the change is related to the new stock.

Slight topic shift, is it possible that the recoil feels stronger bc of the different geometry of the new buttstock?

The bolt comes all the way to the rear when it can travel to the rear far enough for the bolt catch to get in front of the bolt face.

Yes, that is the spacer kit and I have the first buffer installed along with the shorter of the two springs that I have...everything that came with the stock "kit".

I took everything apart and inspected it last night and everything looks right.  No wear or impact points where none shouldn't be.

I am going to test it out again shortly to see if I can see any other difference.  I'll try and see if the geometry of the stock is what is causing the greater (perceived) recoil.  It is POSSIBLE that, using the A2 and A1 stocks, that I was holding if more like a rifle and, since I changed to the shorter configuration, I am holding it more square with my body and feeling more recoil.