new build - springs are short

[john winch]

building a DPMS lower - I understand the springs for the safety and rear take down  should be the same for ar15 and ar10.  I did buy an ar10 lower parts kit...

the take down does not engage the pin - measuring the space between rear plate and take down pin is about an inch on an ar15 but the ar10 lowers I have are more like 1.75" - spring is just too short...

am I missing somthing?

( have not built any ar10 - but have a few ar15's... so the concepts are not new)

[john winch]

On 8/12/2020 at 2:01 PM, Swiftab said:

If your holes are different, make up a spacer pin to add behind the spring. 

I can do that but wanted to make sure  I had the right kit and spring...

thanks

[john winch]

On 8/12/2020 at 1:59 PM, Swiftab said:

Not sure of your lower but on my 308 version, both spring hold are under the grip. (Many parts kits have a 4-40 set screw to capture the spring. 

First pic is AR-15. Holes are on both sides of my thumb.

second pic is 308 lower. You see both holes are under the grip. 

all my ar15's are like yours but the ar10's are not - the safety spring hole is the same location as the ar15 - behind the rear plate

sadly - bought the kits a couple years ago and did not assemble at the time not sure where I bought the lower - but is is DPMS....  (have purchased complete 308s previously been shooting them and hunt with bolt 308)

thanks

[98Z5V]

On 8/12/2020 at 11:01 AM, Swiftab said:

If your holes are different, make up a spacer pin to add behind the spring. 

I had to do this on my Matrix set that I got.  My Matrix lower had the detent hole and spring going in from the back, not the grip area.  Cut off a section of right-sized drill bit - the shank - to the right length.  Dremel cut-off wheel.  Seems that small drill bits are easy to break, but they're a real bitch to cut in two...  

[98Z5V]

4 hours ago, john winch said:

all my ar15's are like yours but the ar10's are not -

Most .308ARs have the detent hole in the grip area, just so you know.  Very, very few of them have the detent hole going in from the back, like AR15s.  Very few.  Spill the brand, so we know. I know you already stated DPMS - but a real DPMS has it going in from the grip area.  You threw the AR-10 term around alot in your first post, too, and there's nothing about this thing that's Armalite, I'll bet.  Terminology matters... It's more than a brand name - it's a pattern change...   

Edited August 15, 2020 by 98Z5V

[DNP]

Make sure it isn’t threaded. Some of them took a threaded screw. Same one used on the bolt catch. That length are up the space. I think my JD had that, but it’s been ten years....so. 

[392heminut]

A piece of coat hanger wire is usually the right diameter and the length you'll need is .700. Snip it a little long and use a file to dress the ends square to get to length. It's not critical if it's a hair shorter or longer.