What is the Lapping Tool of choice for Large Frame AR upper receivers?

[DavidAR10]

Companies that have them:

That AERO M5-E1 dangler seems to be missing its German helmet!

PTG's cooked to order, not before. Great company.

Here's another one.

Looks like a Tipton to me.

I have 4 Aero Precision and 2 ARMALITE large frame upper receivers that I've been thinking of lapping before assembly.

Thanks to those that know!!!

 

[B y r o n]

Stupid question but why did you buy those receivers if you think they need lapping to work?

 

[DavidAR10]

Stupid question but why did you buy those receivers if you think they need lapping to work?

Because every company puts out a lemon once in a while.

Even a CNC monkey works on some Mondays or sometimes has a morning spat with his boyfriend.

Those two brands of receivers are forged, not excreted extruded to a perfectly rectangular turd billet as a starting point. This is the biggest reason.
{just trying to trigger the JPE/KAC etc fans. I will probably own a JPE within the year}

Besides, what is the overall cost of a well designed large frame AR lapping tool when compared to the cost of 6 large frame precision ARs with fair to midland glass w/mounts and mags?

Great question. Forgings don't start out or end up with exact points in the XYZ planes from piece to piece.

 

[palmettoman]

Wheeler

 

[breastroker]

I use the PTG for lapping all my large frame uppers. But some uppers don't need much, my 2A Xanthos uppers needed 3 seconds, while cheaper ones needed a lot more.

I like the PTG, doesn't come with a flex coupling which isn't needed at all.

 

[bfoosh006]

Another vote for the PTG's

And at 30 bucks... I can afford the tool.

If you can get even just a 1/4MOA better groups ( and I have seen much better MOA improvements, as in 1 MOA ) ... then 30 bucks is a bargain.

 

[KYAggie]

Another vote for PTG, I used it on my 6.5 cm with a 2A upper. Mine took more than 3 seconds, but not very long. I’ll never barrel another upper, ar15 or ar10, without lapping no matter how finely built it is suppose to be.

 

[longshot2000]

I like these guys. It could be a branded PTG. Not sure: G&G . Personally, not a huge believer in AR lapping, but it could never hurt, esp with the brands of uppers you are using, you could use every advantage.

 

[Billiam1211]

I used the Pacific Tool & Gauge AR-10 lapping tool on my Aero Precision M5 upper and it worked flawlessly. Fitty% on Youtube has a good video on how to use the tool. I took his advice and mounted the upper vertically so that gravity and downward pressure are applied to the receiver face.

Just a side note, it will not work with Aero Precision M5 Enhanced upper receivers unless you have them turn it down to a slightly smaller diameter.

http://pacifictoolandgauge.com/ar-tools/10318-ar-15-upper-receiver-lapping-tool.html