Barrel Lapping

[Steadfast]

I have a new barrel for my .223 Rem coming soon and will be installed by a gunsmith in may. Because the barrel does not come hand or machined lapped, I am planning on doing it myself. Traditionally this is done by creating a lead slug by melting lead and poring it into a plugged and preheated barrel's muzzle. Now, I have many times used plastic aluminum for bedding and was thinking that the soft epoxy based aluminum might work well as a barrel lap. Has anyone tried this in the past and can anyone foresee any problems that I may have with it or the process of making it. Yes, of course I will remember to wax inside the barrel first.
Thane

 

[paperpuncher]

Lapping is somewhat of an art. If you have not done it you may do more harm than good. Just because it is not lapped doesnt necessarily mean it wont shoot well. I would shoot it and if it does not perform at that point you have nothing to loose

 

[Steadfast]

Lapping is somewhat of an art. If you have not done it you may do more harm than good. Just because it is not lapped doesnt necessarily mean it wont shoot well. I would shoot it and if it does not perform at that point you have nothing to loose

I have done lapping once before. I did it by pressing a lead slug in. My main goal was to remove the tight spots. It worked well. Lapping also helps prevent copper fouling.

 

[Muzzlestuffer]

You can fire lap as well but if you hand lap just be careful with the chamber and muzzle.

 

[Walt Krafft]

The chamber and muzzle end of lapped barrel blanks need 1 inch minimum cut off the muzzle and the chamber cut to get to the properly lapped bore surface. You are likely going to do more harm than good trying to hand lap a finished barrel. IMO.

 

[Alex Wheeler]

Pouring the lead lap is not that hard. If your going to do it, dont reinvent the wheel. Follow the proven process. Messing with epoxy is going to be way more of a hassle than just pouring lead. Its going to take more than one lap as well.

 

[urbanrifleman]

I wouldn't. Barrels do not have to be lapped to shoot tiny. And you can ruin one easily.

 

[Will Henry]

Well, I have lapped a whole bunch of finished barrels and not once was the barrel not improved by the process. Mind you, these were all barrels with identifiable problems which lapping would cure. I have tried a lap of five-minute epoxy, and it worked, but lead worked better. I cast the lead lap on a jag made for the purpose. Usually, I lapped just to improve internal finish, but sometimes, it was to change dimensions. WH

 

[Steadfast]

The chamber and muzzle end of lapped barrel blanks need 1 inch minimum cut off the muzzle and the chamber cut to get to the properly lapped bore surface. You are likely going to do more harm than good trying to hand lap a finished barrel. IMO.

Thanks Walt. This is good information. I didn't realize I could remove so much material from lapping.

 

[Steadfast]

Well, I have lapped a whole bunch of finished barrels and not once was the barrel not improved by the process. Mind you, these were all barrels with identifiable problems which lapping would cure. I have tried a lap of five-minute epoxy, and it worked, but lead worked better. I cast the lead lap on a jag made for the purpose. Usually, I lapped just to improve internal finish, but sometimes, it was to change dimensions. WH

My main purpose for lapping would be to improve the finish and reduce any tight spots.

 

[L.Sherm]

Chances are after you lap it the crown won't be good.
Curious if your worried about the lapping why by a barrel that hasn't been lapped to start with.

 

[Steadfast]

Ok, so based on the responses hear I am reconsidering doing anything to the barrel.

 

[DShortt]

Chances are after you lap it the crown won't be good.
Curious if your worried about the lapping why by a barrel that hasn't been lapped to start with.

Penny wise, pound foolish.

 

[L.Sherm]

Ok, so based on the responses hear I am reconsidering doing anything to the barrel.

If you do lap it before its chambered and crowned

 

[Steadfast]

If you do lap it before its chambered and crowned

Yes and I and would do it from the chamber side and plug the muzzle so the lap couldn't exit.

 

[Bob3700]

Lead is a dead metal and an epoxy material not so much. The lead lap will not be as aggressive as a lap made of epoxy. So depending on the goal of ur lapping choose ur lap carefully.

 

[L.Sherm]

Yes and I and would do it from the chamber side and plug the muzzle so the lap couldn't exit.

It will be fine exiting the muzzle if you do it before chambering and crowning its why an 1" is cut off

 

[Will Henry]

It was in 1971 that I got my copy of "The Muzzleloading Caplock Rifle" by Ned Roberts. In it were pictures and instructions on barrel lapping from some of the old masters (Warner, Billinghurst, Lowe, etc.). I got more info from Wayne Vickery's book "Advanced Gunsmithing" and "The Modern Gunsmith", by James V. Howe. From these books I got a pretty good idea on how they did it and went from there. Over the years, I refined my technique and did things differently, depending on whether the barrel was chambered or not, crowned or not. I came to believe that the right time to lap was actually after the barrel was chambered, but before it was crowned. I used a piece of brass with the primer pocket drilled out to guide and support the rod on chambered barrels. I used a cap with a hole in it for new blanks.
Most quality barrels are, of course, already lapped. Still, if a barrel doesn't perform, lapping can help.. I don't recommend that a person jumps right into it without some careful thought. WH

 

[Dimner]

I have a new barrel for my .223 Rem coming soon and will be installed by a gunsmith in may. Because the barrel does not come hand or machined lapped, I am planning on doing it myself. Traditionally this is done by creating a lead slug by melting lead and poring it into a plugged and preheated barrel's muzzle. Now, I have many times used plastic aluminum for bedding and was thinking that the soft epoxy based aluminum might work well as a barrel lap. Has anyone tried this in the past and can anyone foresee any problems that I may have with it or the process of making it. Yes, of course I will remember to wax inside the barrel first.
Thane

I was worried about this too on my first rebarrel. Chambering and circumstances dictated that I wasn't able to get a hand lapped barrel. Turned out, it wasn't even an issue. That barrel shoots in the .4s

Going forward I have never considered hand lapping to be necessary unless I was going for a benchrest competition rifle.

 

[LVLAaron]

One of the reasons lead works so well, is that the abrasive material sticks in it easily.