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Discussion Starter · #1 ·
I've been trying to find the information and some parts to start/finish an M60 semi build. I have some drawing but they are hand drawn and I don't trust them. I have a JRW trigger assembly but have heard they are no worth messing with. Any help is greatly appreciated.
Thanks
CT
 

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M60

TAKE IT FROM ME DO NOT USE JRW SYSTEM

The hammer that hits the sear is too small to trip it
 

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PhD in Over-Engineering
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Just out of curiosity, what is/are the alternative system(s)?
 

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You might want to check into the ones DLO designed I am not sure if the info is still out there but it worked quite well. Also there is another board member getting an ATF approval for his semi auto design but I will have to go through my PM;s to find the info. Russ
 

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U.S. Ordnance was the only design that worked reliably in Closed bolt semi. they no longer offer them.
If you can find one of the few Springfield armory Semi's that were produced they are worth there weight in gold but fire from an open bolt and are no longer being produced.
Desert Ordnance makes a nice Semi but I believe they are using the U.S. Ord. design.
It is rumored that a 07 in Ca. has redone the JRW firing control group to a beefier system but last I heard he was not offering them for sale.

GW
 

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Discussion Starter · #6 ·
Desert Ordnance was offering a semi receiver last spring at the Creek for $7500 approx. $13500 for a finished complete semi 60, can't afford that. I started this journey about 4 yrs ago and bought the JRW trigger group along with some small parts to start a build on a kit I have. Didn't find out how unreliable it is until after researching into the build a lot deeper. Now, stuck with a dud and still want to build the 60. All help is really appreciated.
 

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The US/Desert Ord design rotates the bolt extension, which holds the sear and drops the firing pin, 90 degrees from the JRW design .
Both designs have a sear in the rear of the bolt, the JRW uses a small hammer in the left rail to smack the sear in the bolt ,he US ord uses a long bar that comes up from the trigger to pull on the sear in bolt. There is a spring on the US Ord bar that forces the bar rearward slightly so after the bolt cycles you have to release the trigger allowing the bar to pop back up and the notch in it to engage the sear again. Very simple but positive method of disconnect.
 

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Discussion Starter · #8 ·
Anyone have any info on Springfield Armory Inc. M60 trunnions? Good, bad? I assume they would be cast? Material? Heat treated?
 
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