Pistol grip/screw not tightening adequately?

Ok so…success! I have successfully tapped/threaded the grip frame screw hole and the rear takedown pin detent/spring hole on all 3 lowers (the small hole right behind the “q-clip” end plate/castle nut). Everything is lookin good now.

Thanks a ton everyone for all the help. As always it’s much appreciated.

- Kris
 
MidwayUSA had a sale on threaded mag release pins for .99c. I bought a few because I hate that particular roll pin. I believe it is a 6x32". The last couple of AR lowers were already tapped for this and it was really easy to install. Turns out you need a 9" long tap to get to this if it isn't tapped already. That tap set me back $20.

Is there guidance on if you can tap the safety detent to retain that spring? Tired of crushing that spring putting the grip on.
I’m not familiar with a roll pin on the mag catch/release. Do you mean the bolt catch by any chance? I know threaded ones of those are pretty popular (I think that will be my next tapping project).

As far as the safety detent spring, I’m sure you could at least somehow bore a hole in the detent to hold the spring tight (maybe with a small drill/reamer or something). I’ve also thought of doing something like this (I keep looking around my rifles just wondering what I can alter/customize/improve😀).
 
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MidwayUSA had a sale on threaded mag release pins for .99c. I bought a few because I hate that particular roll pin. I believe it is a 6x32". The last couple of AR lowers were already tapped for this and it was really easy to install. Turns out you need a 9" long tap to get to this if it isn't tapped already. That tap set me back $20.

Is there guidance on if you can tap the safety detent to retain that spring? Tired of crushing that spring putting the grip on.
If you are going to use a set-screw to secure the spring, the spring will need to be shortened a little, first.
 
As far as the safety detent spring, I’m sure you could at least somehow bore a hole in the detent to hold the spring tight (maybe with a small drill/reamer or something). I’ve also thought of doing something like this (I keep looking around my rifles just wondering what I can alter/customize/improve😀).
Look here for safety detent mod.

 
If you are going to use a set-screw to secure the spring, the spring will need to be shortened a little, first.
Yup. After I tapped the holes I put the detent and then the spring into the hole and then I clipped the spring once it was fully seated in the hole to be flush with the back of the receiver, this way when I screwed the set screw in it was perfect length/tension to get the job done.
 
This probably would have worked, don’t know why I didn’t think of it lol
I looked at a few of my lowers. Three that were finished were threaded all the way thru. A couple of unfinished forged lowers I had in my cache were not. I cant recall where I bought them.
 
I wonder if this was a decision somebody made to avoid a grip screw that's too long from buggering the trigger or safety lever.

It could happen
 
An illustration of a few sizes of taps. L-R: 6-1.00, 6-1.00, 1/4-20, 1/4-28. The stubby 6x1 may have been rescued from a broken tap, I can't remember. Note the first 6x1 is unaltered--by comparison, the 1/4-28 may have had the point ground off.

1/4" is the outer diam. of the tap (approximately), -20 is the number of threads per inch. (TPI)
Regarding metric, 6mm is OD, 1.00 is the number of mm between threads or "thread pitch".

taps.jpg
 
Yes, bolt catch. Sorry for the wrong terminology. I general have no love for the AR yet I have somehow built enough of them that I basically dump all the parts on the table and go to work. I don't trouble myself with proper part names.

The ball detent is interesting. Not sure I am ready to drill out a perfectly good lower to make that mod. I blatantly copied Aero Precision's Bolt Release screw and captured takedown detent. I think the bolt release screw was first seen on an Aero AR-10 lower. This seems to work just fine on the AR-15 but it takes a 9" or longer tap to get at it correctly.
 
Yes, bolt catch. Sorry for the wrong terminology. I general have no love for the AR yet I have somehow built enough of them that I basically dump all the parts on the table and go to work. I don't trouble myself with proper part names.

The ball detent is interesting. Not sure I am ready to drill out a perfectly good lower to make that mod. I blatantly copied Aero Precision's Bolt Release screw and captured takedown detent. I think the bolt release screw was first seen on an Aero AR-10 lower. This seems to work just fine on the AR-15 but it takes a 9" or longer tap to get at it correctly.
Yes I was going to ask you actually, what kind of tap exactly did you need to use for doing the bolt catch pin hole threading? I know you said 9” and 6-32. Did it have a specific style or shape or anything (to be able to reach the hole and still be turnable with a tap wrench. Kinda like how the pin punches for that pin/hole are specialized to fit flush against the gun and be long enough to still be able to be tapped)?

Also the ball detents for the safety, I used to build paintball guns called autocockers when I was a kid and they used that ball style detent for the safety’s so I’m actually familiar with it.
 
I got the tap on ebay, 6-32, but verify the threads on the screw you have. I think I measured 7" to clear the back of the receiver and enough to grip the tap. 9" and 12" long taps were all I saw long enough. A 6" is not long enough, don't buy it thinking you can get by. The tap has to be parallel to the side of the receiver. Long enough to clear the back of the receiver is the only way to tap it.

Your choices of long taps is limited. The tap I got was a tapered nose. You can't cut enough threads with a tapered tap. I ground off a few threads to make it a plug profile and it worked fine. You only tap the back half of hump. The front half stays untapped.

I searched eBay for a 6-32 long tap and a suitable one popped up. It can be frustrating searching for an exact item on the more convenient places. They feel the need to give you 20 sponsored listing that are not what you need.

Clear as mud?
 
I got the tap on ebay, 6-32, but verify the threads on the screw you have. I think I measured 7" to clear the back of the receiver and enough to grip the tap. 9" and 12" long taps were all I saw long enough. A 6" is not long enough, don't buy it thinking you can get by. The tap has to be parallel to the side of the receiver. Long enough to clear the back of the receiver is the only way to tap it.

Your choices of long taps is limited. The tap I got was a tapered nose. You can't cut enough threads with a tapered tap. I ground off a few threads to make it a plug profile and it worked fine. You only tap the back half of hump. The front half stays untapped.

I searched eBay for a 6-32 long tap and a suitable one popped up. It can be frustrating searching for an exact item on the more convenient places. They feel the need to give you 20 sponsored listing that are not what you need.

Clear as mud?
Cool, thank you. Much appreciated. Yeah that’s what I was wondering basically, how long it needed to be to clear the receiver and be able to stay flush and if there was any type of special shape/type it needed to be.

I’ll probably get the 6-32 cuz I’m gonna try to find the aero/brownells screw.

I hear you too about some of these retailers. I usually go to McMaster or grainger for everything because everything I get from there always seems to be quality, even when I don’t know exactly what I want/need and I just choose from a list. You can’t do that with Home Depot or Amazon or anywhere like that, you’ll wind up with crap real quick.
 
I got AR Stoner screws from MidwayUSA only because they were on sale for .99c. I have no idea what thread pitch is used on other brand screws, it was 6-32 on the screw I had. Aero/Brownells should list the thread size, I don't know. It is not a Mil Spec standard so it could be anything.

Verify the threads, get a tap at least 7" long. I would measure to verify my measurements. All I remember is that it was 6 inches to the back of the reciever and a 6 inch long tap will not be long enough because the collet of the tap handle will make it tilt out.

You only tap the back half of the bump. 0] [0-this half only
 
I got AR Stoner screws from MidwayUSA only because they were on sale for .99c. I have no idea what thread pitch is used on other brand screws, it was 6-32 on the screw I had. Aero/Brownells should list the thread size, I don't know. It is not a Mil Spec standard so it could be anything.

Verify the threads, get a tap at least 7" long. I would measure to verify my measurements. All I remember is that it was 6 inches to the back of the reciever and a 6 inch long tap will not be long enough because the collet of the tap handle will make it tilt out.

You only tap the back half of the bump. 0] [0-this half only
Awesome! Thanks. I’ll make a note about only tapping the back portion (closest to rear of receiver).

Also, my mistake, I thought you had said you had an aero screw from brownells. I meant to say I’m gonna try to find whichever one you mentioned, so I’m gonna check midway for AR stoner. Thanks again for all the help. Much appreciated as always.
 
I wonder if this was a decision somebody made to avoid a grip screw that's too long from buggering the trigger or safety lever.

It could happen
Another AR grip screw tale:

My dad was primarily a bench-rest shooter and due to health is no longer able to shoot.

He used grip screws with take-up adjustment screws in his ARs. They work by pushing up on the trigger bottom and can make the gun dangerous if one goes too far.

He had a few NDs with them, and was recently diagnosed with dementia so I "inherited" his builds, and have been charged with liquidating his guns and gear. Won't have to worry about him shooting anymore holes through the roof!

For the record, the adjustment grip screws can be made to work properly and be safe. Just can't push beyond certain limits. I would not use such a device in any AR meant for self-defense. For a dedicated target rifle, it might be nice.
 
Another AR grip screw tale:

My dad was primarily a bench-rest shooter and due to health is no longer able to shoot.

He used grip screws with take-up adjustment screws in his ARs. They work by pushing up on the trigger bottom and can make the gun dangerous if one goes too far.

He had a few NDs with them, and was recently diagnosed with dementia so I "inherited" his builds, and have been charged with liquidating his guns and gear. Won't have to worry about him shooting anymore holes through the roof!

For the record, the adjustment grip screws can be made to work properly and be safe. Just can't push beyond certain limits. I would not use such a device in any AR meant for self-defense. For a dedicated target rifle, it might be nice.
I played around with one of those and came to the same conclusion. Dangerous as Hell. I noticed that recoil/vibration could affect the take-up screw. I'd liken it to how some trigger pins can walk when you are shooting a lot. I took it out and tossed in the parts bin for things that broke or didnt work.
 
If my memory is correct, the mil spec for the pistol grip screw is 1" long. Anderson was notorious for not threading the receivers all of the way and using a 3/4" long screw.

The easy fix is to just run a tap down the hole to finish threading it all of the way so a standard grip screw fits.
 
Even easier is use a 3/4 inch grip screw. It costs 50 cents and takes 30 seconds to solve the problem.

When I go to the grocery store 5 miles away, I don't turn in the opposite direction out of my driveway, traveling 30,000 miles to circumnavigate the Earth because it's easier to make a right hand turn into the store parking lot vs. a left.
 
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