Just bought a Colt DOE upper and bolt and want to run it on a M16.
I really like the look of shorty M16s

Obviously I don't want to drill into the lower so as to lower its value so a drop in 9mm block is called for.
Which one works well without marring the lower ? If I have to give up bolt hold open on last shot thats fine.
Also don't know if the DOE bolt is ramped or not. I may buy a CMMG (?) bolt anyhow. Is this the best one ?
Any other non-permanent mods to be performed ?

Thanks.

Check out the Hahn Precision mag blocks.  They are super nice, bolt hold open is not a problem, does not mar the receiver.

http://www.brownells.com/rifle-parts/bolt-parts/caliber-conversion-kits/ar-15-dedicated-9mm-conversion-block-prod24937.aspx



It just drops in.

I just bumped a thread on the VM Hy-tech which I am probably going to pass on now as the reviews for these Hahns are very favorable.
I assume the drop in is the way to go ? A little more work  but a more reliable capture and no set screws.

Now looking at ways to protect the lower.
Probably a set of anti-walk pins which is probably a good idea even if not converted to 9mm.

Hydraulic buffers are said to lower rate of fire, maintain better accuracy and reduce wear and tear.
This one is on sale
http://loadoutroom.com/11622/crosshair-hydraulic-buffer-shoot-straight-protect-carbine/

at the same place that offers this stainless steel one.

http://www.buffertech.com/KynSHOT-AR15-Collapsible-Stock-Precision-Hydraulic-Recoil-Damper-P325.aspx

(Thinking out loud here)

Edit; just talked to the Buffer technologies rep who said neither are specifically designed for 9MM or any other cartridge other than 5.56.

Double check but I think the drop in does not have last round bolt hold open, which may or may not be a big deal to you.

I'll call them.
Hold open on last shot is down my priority list.
Not screwing up /marking the receiver is top.

Thanks.

This is my setup.  It runs perfectly with 115gr, 124gr and 147gr ammo.

The Colt AR15 Model 614 (full auto) lower is not affected at all.

The important parts:

Hahn bottom loading conversion block
Colt 10.5" 9mm barreled upper (Colt Part #SP62993)
Colt 9mm BCG (Colt Part #SP62860) ramped by m60joe <<<< must be ramped !!!
Colt 9mm Buffer Assembly (Colt Part #SP62913)
Colt 9mm Receiver Extension Spacer (Colt Part #SP400211)
Wolff XP Spring
Geissele SSF trigger group and Geissele pins only

Accessories:

Daniel Defense EZ-CAR 7.0 rail
Daniel Defense VFG
MagPul CTR mil-spec stock
Troy flip-up rear sight
AimPoint PRO

Magazines:

Colt, Metalform or Brownells only.

The bolt will hold open after last shot fired

Thanks for the responses.

Haun blocks have always worked for me. They are traditionally the most expensive, and they also traditionally always work. You get what you pay for. The CMMG ones are cheaper and I have also heard good things. 6 one way half a dozen the other.