Ramping a 9mm Bolt.

[Paulinski]

I'm in the process if assembling a 10.5" 9mm SBR. I'm using Stag lower with Stag LPK with exception of hammer and K&S pin set.

I have a factory 10.5" 9mm RRA upper. I was wondering if ramping the 9mm bolt is a benefit. What does ramping accomplish? Does anyone have the drawing of properly ramped bolt so I can give it to my gunsmith?

Thanks in advance

Paul

[TacDoc]

The benefits of a ramped 9mm bolt:
1. Less stress to the hammer pin holes in your receiver.
2. You can use any FCG you want, it eliminates the need to use a 9mm hammer.

My bolt was ramped by Steve/Adco and I'm very pleased with the results. I run a RRA 2-stage trigger group without any issues. He charges $35 for the service and have a fast turn around time.

There is a member in TOS named MGP that charges $50 (I'm not 100% sure about this price) and have same day turn around time.

If I were you I'll let a professional with experience do this job. Its really easy to affect the timing of the weapon with a wrong angled ramp. Just my 2 cents...

[TY44934]

What angle is the ramp in relation to the carrier? how wide is the cut? I sure its an easy cut with a mill.

[MH64]

Will a ramped bolt work with a standard Colt 9mm hammer?

[trg42]

Besides recocking the hammer over a much longer bolt travel ( an thus being gentler on your hammer pins ) the reason I ramped was so I can run standard / aftermarket trigger groups

The problem with the RRA bolt is there is a notch across the bottom of the bolt. I have no clue why its there . See pic below. The problem is with some triggers like the CMC drop in, the notch catches the hammer when it goes forward and jams up the gun so bad you need to drop both the tackdown and pivot pin to free it up





After ramping, the hammer cannot catch . I use this upper on lowers with a RRA 2 stage, CMC single stage, LMT standard . Works great with all three




I ramped mine 5deg . Length of ramp dupicates approx. a standard AR15 223 Carrier ramp

[Paulinski]

Thanks for the info above.

Will a stock RRA 9mm hammer work with ramped bolt? My main issue is to reduce the wear on hammer pin hole.

Paul

[trg42]

Thanks for the info above.

Will a stock RRA 9mm hammer work with ramped bolt? My main issue is to reduce the wear on hammer pin hole.

Paul

Sorry but after I ramped my bolt I didn't bother to install my 9mm hammer so I can't answer your questions