Bolt Hold Open For 27a1

[anticus]

I want to install the bolt hold open mod for my SBR. Is there a description of how to do the install anywhere and where does one get the parts ? I'd send it to PK or Damon but don't want to wait that long if it's not a major undertaking. The 28 frame is already fitted to the receiver and the gun runs like a Singer. The hold open is the finishing touch it needs.

 

[Ghostdancer]

Okay, I'm the newbie here, but what does a bolt hold open do that pulling the bolt back on an empty magazine doesn't do? Not being a smartie on this, just curious.

Steve

[Norm]

Ghostdancer,

 

Stick mags do hold the bolt open after the last round is fired, but drum magazines DO NOT.

 

This was never a problem on SMGs as they fire from an open bolt. When the drum is empty, simply cock the actuator and remove the drum.

 

Closed bolt guns (27A1s) are not capable of doing this, thus the bolt falls forward after you cock the gun. There is a device called a "third hand" used to lock the bolt back (like a stick mag does) so you can get a drum out of a 27A1.

 

As a nice side effect, the "bolt hold open" modification makes a semi-auto look more like a full-auto gun.

 

Norm

 

[M1Brian]

anticus

 

If your talking semi here I had PK do mine. From what I can see (and I'm an mechanic not a gunsmith) it appears to be a modified pawl installed in the gun. I'm not sure if any machineing was done to the selector shaft or not. Best to ask Damon or PK direct. On a 27a1 there is a bolt hold open on the top of the reciever. If you pull the bolt all the way back and lift up on the cheese grader knob the bolt is suppose to stay back. I've heard from this board that feature is very unreliable and wear occurs to the larger hole.

It must be nice to live in a sbr state in MI I had to go the OAL 16" barrel and welded comp and to put icing on the cake with the 28 stock assy. removed it was a 1/4" shy of 30" oal. I had to take it to the local pd and have it registered like you would a hand gun. Not that it was a problem doing that the officers all thought it looked really cool. It just would have liked going the sbr route.

 

M1Brian

 

[anticus]

M1 Brian,

 

I feel your pain. I lived in Illinois for several years, back when I could have afforded the real thing,but state law forbade it.

Missouri only requires you to have a C&R license to possess any transferable, relic or not, but I can't afford the MG's now so I went the SBR route. The process was relatively painless. What I can't do are the big technical things, like swapping barrels and such. I know PK and Damon can do wonders, it's the turnaround time that's discouraging.

But maybe I can do the hold open mod with the right info,tools,etc.

[Grey Crow]

The modification also requires opening the frame to give more space for an additional spring, and a small washer for a spacer. The frame also needs drilled for a rocker switch.

 

[anticus]

My SBR has a '28 frame for the lower so the selector hole is present. The pawl has a spacer but lacks the springs and relief cut.

[Grey Crow]

A 28 frame is my next upgrade, I don't care for the configuration of the M1A1 style frame.