I had an A2 20" HBAR, which over the past 8 months has evolved into a 14.5" M4gery with a telestock.

I want to reuse the A2 stock, buffer tube, buffer, and spring.....but...I want to build an A3 reciever as this next project will definitely be scoped.  I am thinking about getting a complete upper with the A3 reciever but just want to confirm that there wont be and issues with using the old A2 stock assembly. I would think it will work, but since I havent seen an A3 up close yet, I wanted to make sure....and you guys know best.

Thanks for you help.

Oh, and here is what a 20" HBAR turns into when stupid gun laws expire.....

A lower is a lower is a lower, the upper has nuthing to do with the lower.

Yes, your A2 will mount to any lower ever made, as this is where the "stock" mounts on an AR15/M16.

Mike

PS - suspect with abit of sober thought you'd have arrived at the same conclusion....

I was thinking more in terms of how the A2 buffer will work with the A3 upper....I figured that it would physically bolt up, but from what I can see, an A3 buffer and spring are shorter than the A2. My concern is that the spring is too strong (because it is longer)

Can I reuse the same spring and buffer?

Your confusing the upper with parts such as the A2 length buffer and spring for which there's not a problem.

An A2 stock has the full length buffer and buffer spring, a M4 collapsible stock (as yours above) has a carbine buffer (shorter than the A2) and a carbine buffer spring (same as buffer, shorter), these are the parts it's important to differentiate between.

The only difference between the A2 upper ya have above and the A3 upper ya want is the lack of a sight and carry handle and the addition of the flat-top mounting area on the A3.

One has nuthing to do with the other...... and there's NO difference between the way the A2 upper interfaces with the lower than an A3 will, it will work fine.

Yes your A2 stock buffer and spring will work, as noted above.

Mike

Cool...thanks...I was concerned that actual bolt in an A3 had a different total mass and that it was designed for a specific length spring. I figured it would be cool but wanted some feedback before commiting to anything.

Thanks again