8.5" pistol-length upper????

[fergie.17]

I was looking at a PSA 8.5" pistol-length upper in 5.56 NATO. can I just swap out the 16" carbine length upper I have for this one and be good to go??? would I need to change buffer weight??? (3 oz at the moment) buffer spring for something else???
I was just looking for something to have fun with at a 100yards max with and thought it would be fun to have a short barrel ar. should I expect problems????
thanks

 

[hbean]

You should be fine, can't really tell until you actually try it, you could upgrade your buffer to a heavier one before hand, but it might be a waste of money.

 

[fergie.17]

thanks
I've been trying to read about the shorter barrels and some say that they may need an adjustable gas block??? they can be finicky........ that's really what I'm worried about, don't know enough about the ar platform to start screwing around with that.
I'm not even sure if I go to a heavier buffer even with the carbine length barrels what really happens.......
total newb to them...... LOL
just installed a LPK and mil-spec buffer tube kit on a stripped lower for the first time the other day.

 

[bushwacker's]

You will not need a adjustable gas block or a different buffer weight , you will simply attach it your lower and 9/10 times will be good to go , I have a 7.5" .300AAC Blk out custom build we just took to the range operated flawlessly , same with 762x.39 my buddy pinned it onto his lower and it has run perfectly since I think his is a PSA I might be wrong but most issues have been worked out on commercial uppers .
Bushy

 

[CobraGT]

I swap my 7.5" 7.62x39 PSA upper all the time with my IUR 5.56 upper, on a Colt Canada lower, with no problems whatsoever. Same buffer.

 

[rdavidson]

I had to change to h2 buffer

 

[fergie.17]

thanks for the reply guys.
how would I know if I needed a new heavier buffer??? what happens with the lighter buffer???

 

[bushwacker's]

Many factors dictate fine tuning buffer weights for precision rifles Bolt design and bolt weight , loads , calibre put 1 round in your magazine fire it and see if you lock open if your not short stroking the bolt should lock open .
If your buffer/ Spring combo is too soft which will effect recoil you can test by sticking a small piece of modelling clay on the end of your buffer if its squashed than your spring buffer weight is too heavy / not stiff enough .
The Majority of off the shelf uppers / BCG's are designed to work perfectly with mil spec buffer/ spring combo's unless your rifle fails to function correctly you really don't have to worry about anything except buying more ammo

bushy

When buffer / spring combo's become more vital is when your start to really work with different loads +++ super loads and subsonic loads etc than fine tuning becomes vital

 

[fergie.17]

thanks
i'll have to pick one up and give it a go and see how it works.