AR-15 has got me frustrated.

by Hobie ⌂ @, Shenandoah Valley of Virginia, Thursday, July 27, 2017, 20:48 (142 days ago)

I wanted to install a Timney packet trigger in my Delton lower but there is a dimensional difference, or so it seems, between the hole center to center in the receiver and the pin holes in the packet. Arrrrgh!!!




by Miles @, Thursday, July 27, 2017, 22:12 (142 days ago) @ Hobie

Bear with me as I don't know what you've tested, or not.

First, make sure the hammer/trigger pins can actually go through the holes in the trigger pack and receiver separately.
If so, one or the other may be out of spec, or, you may have run into tolerance stack, where one part is at max and the other at min tolerance.

If you have a set of dial calipers, measure the distance from far edge to far edge of the holes on the trigger and receiver, then subtract .156 for the center to center distance.

Your measurements should be very close to .900" +/- .001"

The math works out like this:

Solve for Hypotenuse of Triangle with
A horizontal distance CtoC Hammer/Trigger pin hole = .843
B vertical distance height difference of holes = .314
C Hypotenuse X
Standard formula A².710649 +B².098596 = C².809245
√.809245 =.899580

Let us know the results!

I'll have to check it tonight.

by Hobie_, Friday, July 28, 2017, 07:58 (141 days ago) @ Miles


Ok, so it will be tomorrow, sometime tomorrow...

by Hobie ⌂ @, Shenandoah Valley of Virginia, Friday, July 28, 2017, 21:11 (141 days ago) @ Miles




Lined up on the outside of the lower, with the pins, the

by Hobie ⌂ @, Shenandoah Valley of Virginia, Saturday, July 29, 2017, 17:12 (140 days ago) @ Hobie

trigger "fits" but it won't fit down in the well. I'm going to take it to work on Monday and try it in another couple of lowers but I suspect that the interior of the Delton lower is a shade not deep enough and further than the bottom is a bit asymmetrical, right and left and not quite as deep on the left as on the right. No, I didn't measure, just ran out of time and put the original trigger back in so that the firearm would be functional. Might get a new lower but not excited about that. Might get one of the really inexpensive ARs and see if it will go in one of those. Our gunsmith has installed many of these triggers and this is the first instance of this he's seen.



Send it back...

by bmize, Saturday, July 29, 2017, 17:20 (140 days ago) @ Hobie

Back during the rush to stock up in 12' or so, we got a bad batch from Delton. Called and got a RA number and were replaced.
My 2 built from their stripped lowers were great, though I did not but one of the "modular/box" trigger in either. I have put a couple of the RISE box trigger in a few Anderson lowers with no problems

I've had this lower for 9+ years. A little late to send it

by Hobie ⌂ @, Shenandoah Valley of Virginia, Saturday, July 29, 2017, 22:17 (140 days ago) @ bmize

back I think. It works fine with the standard trigger, just not a great trigger.



Call DelTon anyway

by Miles @, Sunday, July 30, 2017, 18:03 (139 days ago) @ Hobie

Never considered that the interior milling might not allow a unitary hammer/trigger to fit as I've never worked with them.

In any case, call DelTon anyway.

You never know, and if you don't ask the answer is already 'No'.

That is true.

by Hobie ⌂ @, Shenandoah Valley of Virginia, Sunday, July 30, 2017, 18:41 (139 days ago) @ Miles




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