I’ve done a number of these. In fact, I did an AR10 and AR15 clone this weekend. Don’t remove and then re-insert the tool from the receiver like he did while lapping. You will get lapping compound on the inside of the receiver and lap the internals – something that doesn’t need it. Or you will have to clean and re-lube the tool each time which is a pain. Ask me how I know.
Instead, just remove the lapping tool within the bounds of the rebated part of the tool. Clean the top of the receiver with a rag and solvent and check it with a flashlight to insure the whole surface is lapped. This can take a while with 220 grit lapping compound. Even one that isn’t out much can easily take 5 minutes of lapping.
This article is filed under the category(s) AR-15s and was published March 3rd, 2019 by Herschel Smith.
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On March 4, 2019 at 7:53 pm, Ned said:
I’ve done a number of these. In fact, I did an AR10 and AR15 clone this weekend. Don’t remove and then re-insert the tool from the receiver like he did while lapping. You will get lapping compound on the inside of the receiver and lap the internals – something that doesn’t need it. Or you will have to clean and re-lube the tool each time which is a pain. Ask me how I know.
Instead, just remove the lapping tool within the bounds of the rebated part of the tool. Clean the top of the receiver with a rag and solvent and check it with a flashlight to insure the whole surface is lapped. This can take a while with 220 grit lapping compound. Even one that isn’t out much can easily take 5 minutes of lapping.