Ar15 Lower: Jumping In

[n3480h]

The set screw doesn't tension the pin itself, rather it tensions the rear lug. Pressing up on the lug theoretically removes the slop between the upper and lower at that point. (If I'm understanding the procedure correctly.)
As for overtravel screws, I have seen s 1/4-28 set screw put in on top (before) the grip screw and adjusted in such a way as to limit the trigger take-up. No help on the overtravel though.

Oh, ok. That makes sense, and would not be hard to do. Guess I won't know if my receiver fitment will be sloppy or not until they are pinned together. I've seen some "discussions" on the issue elsewhere, and in the end it seems a loose fit has no effect on accuracy, but it can be an annoyance. But this is why we want our pins to fit fairly tightly into reamed pin holes, yes? As to the trigger, it appears that there needs to be some overtravel to allow the AR trigger to reset. Perhaps it would be wiser to concentrate on very smooth honed engagement surfaces and FC spring tuning.

On a related subject, it is currently not legal to own or use a silencer in Iowa. However, Iowa's House recently passed a number of new gun bills, (in the right direction). Now if the senate agrees, they will become law. One of the changes will allow the use of silencers if the device and the owner comply with NFA regulation. This would allow me to add one to the 300 Blackout - which would be a very good thing. It would be great fun to load and shoot sub-sonic rounds.

Tom

 

[planeflyer21]

November-three-four-eight-zero-Hotel, Arizona passed something similar a few years ago. We may now use properly registered suppressors while hunting.

 

[Rick Leslie]

I found the Accu-wedges on fleabay for pennies each. (I'm a bit lazy.)

And suppressors are now legal to hunt with in Ga. as well. So my first Form ! build is just kicking off.

 

[sgisler]

And suppressors are now legal to hunt with in Ga. as well. So my first Form ! build is just kicking off.

Would love to see that! (If it wouldn't cause any trouble)


Stan,
Sent from my iPhone using Tapatalk

 

[Rick Leslie]

Would love to see that! (If it wouldn't cause any trouble)

I'll have to check forum rules on NFA stuff. Most don't like the "How to" part but a finished product may be OK.

 

[n3480h]

Well, the old guy got lucky. Again. Finished the machine work on the lower today, but pretty much drove myself nuts obsessing about the fit to the upper. At this point I am very happy that I chose to mill a 0% casting, and here's why: The (vertical) fit of the upper to the lower is primarily dictated by the pin locations, BUT . . . it is possible to prevent ANY sloppiness or rattle in the fit by paying attention to the width of the upper pin lugs. All I did was to match that width when I milled out the pocket the rear lug fits into, +.001". Fits even better than my Armalite, with only enough room for a thin coat of Ceracoat. It absolutely does not rattle or move, yet it goes together easily. Very lucky. Now its on to removing the forging lines to smooth all the exterior surfaces, then sandblast, tap the buffer bore, and Ceracoat. I bought the paint at Brownells, so I ordered the tap at the same time.

Tom

 

[ScrapMetal]

Looks great. I'll be looking forward to seeing it finished.

-Ron

 

[brav65]

How do you plan to engrave a serial number? Looks great by the way!

 

[n3480h]

How do you plan to engrave a serial number? Looks great by the way!

There is a local watch and clock shop that does computer generated metal engraving. Last time I had something engraved there it was $12-13. I don't know if it is conventional or laser engraving, but it is very professional looking. Anyone here care to comment on engraving before or after Ceracoat?

Thanks for the kind encouragement, guys.

Tom

 

[brav65]

There is a local watch and clock shop that does computer generated metal engraving. Last time I had something engraved there it was $12-13. I don't know if it is conventional or laser engraving, but it is very professional looking. Anyone here care to comment on engraving before or after Ceracoat?

Thanks for the kind encouragement, guys.

Tom

Tom I would check with them as many places will not touch a home made gun part. By working on a completed lower they are doing work to a firearm and can get unwanted attention from our favorite government agency.