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Posted: 1/27/2010 7:36:51 AM EDT
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I have the dreaded Notched hammers in all my lowers. CMMG sells the hammer seperately. Does the trigger and hammer have to be replaced as a set or can I just replace the hammer with no fitting? I have RRA single stage LPK's.
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Quoted:
I tried my new 22 build with a RRA notched hammer, no go - I couldn't even rack the bolt without it hanging up on the notch. I dropped in a DPMS rounded hammer and it runs fine now. . I got a dumb question. what prevents a person from grinding the notch off the hammer, so the rear profile is smooth? why wouldn't that work? 
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Quoted:
Quoted:
I tried my new 22 build with a RRA notched hammer, no go - I couldn't even rack the bolt without it hanging up on the notch. I dropped in a DPMS rounded hammer and it runs fine now. . I got a dumb question. what prevents a person from grinding the notch off the hammer, so the rear profile is smooth? why wouldn't that work?
I've been wondering the same thing? Why not grind the hook offf the back and round the top? Wouldn't that make it a short speed hammer? My notched hammer looks like the top of the face is slightly below center on the firing pin anyway. I haven't taken it to the range for testing because of the notched hammer. |
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Quoted:
Quoted:
Quoted:
I tried my new 22 build with a RRA notched hammer, no go - I couldn't even rack the bolt without it hanging up on the notch. I dropped in a DPMS rounded hammer and it runs fine now. . I got a dumb question. what prevents a person from grinding the notch off the hammer, so the rear profile is smooth? why wouldn't that work?
I've been wondering the same thing? Why not grind the hook offf the back and round the top? Wouldn't that make it a short speed hammer? My notched hammer looks like the top of the face is slightly below center on the firing pin anyway. I haven't taken it to the range for testing because of the notched hammer. I believe you'd need to add metal (fill in the notch), not round it off with a grinder. My Tac-Sol uppers will not reset a notched hammer. Seems like that means the bolt is not rotating the hammer enough to engage the sear. My question is: Who makes a nice, crisp trigger that works reliably with the Tac-Sol uppers? |
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Quoted:
Quoted:
I tried my new 22 build with a RRA notched hammer, no go - I couldn't even rack the bolt without it hanging up on the notch. I dropped in a DPMS rounded hammer and it runs fine now. . I got a dumb question. what prevents a person from grinding the notch off the hammer, so the rear profile is smooth? why wouldn't that work?
That was my first thought, too - until someone pointed out that a notched hammer barely contacted the firing pin on a 22 as it is. It was explained to me that the rounded hammer has two functions - to not snag the underside of the bolt and to provide full firing pin contact. |
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[/quote] That was my first thought, too - until someone pointed out that a notched hammer barely contacted the firing pin on a 22 as it is. It was explained to me that the rounded hammer has two functions - to not snag the underside of the bolt and to provide full firing pin contact.[/quote] ok, the front of the notched hammer (I'm referring to the hook that points toward the hammer face as the "notched" part) is smooth, the firing pin in the 22 is in the same spot (roughly center of the bore) as the .223, if the hook is ground flat, how does that have anything to do with "firing pin contact"? I'm trying to understand the geometry being referred to. I'm building a 22lr lower, using a Doublestar lower, and I have a LPK with notched hammer. I've already ground off the hook, I'll try it tomorrow & see what happens. dry-firing it, lower only, manually cocking it and with a leather pad for the hammer to fall against, it works fine. |
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Quoted:
ok, the front of the notched hammer (I'm referring to the hook that points toward the hammer face as the "notched" part) is smooth, the firing pin in the 22 is in the same spot (roughly center of the bore) as the .223, if the hook is ground flat, how does that have anything to do with "firing pin contact"? I'm trying to understand the geometry being referred to. I'm building a 22lr lower, using a Doublestar lower, and I have a LPK with notched hammer. I've already ground off the hook, I'll try it tomorrow & see what happens. dry-firing it, lower only, manually cocking it and with a leather pad for the hammer to fall against, it works fine. One word - rimfire.  The firing pin on a .22LR AR is at the top of the chamber.
I'm not sure what you're describing with the "hook" - the rounded/notched description only refers to the actual face of the hammer. We may be talking about different things. This is a notched hammer: 
This is a rounded hammer: 
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I'm not sure what you're describing with the "hook" - the rounded/notched description only refers to the actual face of the hammer. We may be talking about different things. This is a notched hammer: http://media.midwayusa.com/ProductImages/Medium/852181.jpg This is a rounded hammer: http://media.midwayusa.com/ProductImages/Medium/485437.jpg [/quote] Heavyduty, you are exactly right. I only have rounded-! the pics show me what I was mistaken about. raffica45 |
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