Hand Lap Your Own Barrel?

Reelamin

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Aaaaannnnnndddddd We have a winner right there BFD. LOL....thanks I guess I can now go out in the shop and work without worry.
 

JMGamesniper19

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Gosh! Talking about me like I'm not in the room! 😄




I just thought, because.

Nope

Nope

I like to F around and find out about most things, but not this stuff! :cool:

What specs? 😄

I didn't know what lapping a barrel involved. I just thought you could use a cleaning rod, patch, and flitz. Tools? Didn't know I needed any!

But now I discover you don't want the barrel smooth because it adds friction...jeesh! LOL

I've learned about the Tubb's fire lapping method. It's a good day! I've learned!
Probably one of the funnest discussion threads I have been a part of in a long time. l make rifles, and I have a lot of experience with barrel making. I would say this.

Lapping is not something I recommend you learn - the pros do it 50 times per day and they don't even get it right some of the time. Take the time and effort on learning other things and honestly; buy a good barrel with the money you would have spent on gauges and F-ing it up and let the pros do the lapping.
 

ejg

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I do not buy into the gritty bullets. I have however done a lot of precision lapping in general Engineering as well as advanced ceramics. Most of my factory barrels I hand polish/lapp. I use Peek a very fine (aluminiumoxide I presume) paste or liquid. Wrap cloth or paper very tight around a brush, add peek and give a few strokes before repeating. Stop about 2" before the muzzle. On the last stroke it goes out the muzzle. Once the barrel feels smooth, clean and shoot it.
My new Rem 300wm long range was spewing around 2-3" at 200yds and after the treatment my first group was well under 1/2" at 105m.
I have been doing this since about 15 years now on new rifles or those that seem to go off badly for whatever reason, if that doesn't work the barrel goes in the bin.

The rem 300, we don't have any ranges near us so I mostly check/zero off the hood of the Landy.

kFJYB0A.jpg


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On the same day I checked 75ELD out of my new 22-250 Bergara 1/8 barrel in a T3 action. She was also polished/lapped in the same manner.

96HVFcp.jpg


edi
 

DJ Fergus

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How effective would some Flitz be on a new factory made rifle? Maybe a 5-6 passes on a patch wrapped around a caliber sized brush?
Around 20 years ago, I tried flitz polish in a barrel. Accuracy got worse. Im very hesitant about anything of that nature. Some folks use the tubbs Polish bullets. I probably wouldn't try them myself but I guess it would hurt if it was a last ditch effort.
 

BFD Guns

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Probably one of the funnest discussion threads I have been a part of in a long time. l make rifles, and I have a lot of experience with barrel making. I would say this.

Lapping is not something I recommend you learn - the pros do it 50 times per day and they don't even get it right some of the time. Take the time and effort on learning other things and honestly; buy a good barrel with the money you would have spent on gauges and F-ing it up and let the pros do the lapping.
I am glad I could make the forums more enjoyable for you! It seems the common trend, away from LRH, but still is at the cusp many times here, is people just waiting to get triggered and rage on some typed content. I try to treat all members as if we were in the same room.
 

SSgt G Cody

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As I understand it, lapping and polishing is usually needed only on lower quality factory rifles to remove any machining "Flash". This is usually on a new rifle that has poor accuracy! Almost all high quality custom barrels are lapped at the factory. The chamber is only semi-polished. The feed ramp is usually highly polished. I believe the polishing agent is Alumina (Aluminum Oxide). Grit size is 360, 600, then 1000, according to my gunsmith friend!
 

ejg

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Probably one of the funnest discussion threads I have been a part of in a long time. l make rifles, and I have a lot of experience with barrel making. I would say this.

Lapping is not something I recommend you learn - the pros do it 50 times per day and they don't even get it right some of the time. Take the time and effort on learning other things and honestly; buy a good barrel with the money you would have spent on gauges and F-ing it up and let the pros do the lapping.
Agree, it would take a bit of time to learn the skill of lapping a barrel with say a lead slug. Less risk is using a patch with a fine polish which is more or less polishing away copper/carbon fouling as well as slight removal of uneven spots. One needs to limit the amount of material removal... Important is also to know if the process is needed or not.

I have seen the lapping machines at cut barrel makers in Europe as well as the US it is not hobby gear. Was also very lucky to have worked with the guy who made the seals/ valves for your first moon landing air supply in the suits. Allowed was 1 litre of helium leakage in 30 years and this Swiss guy was chosen to make them. We needed the same or similar process for our ceramic seals.
edi
 

JMGamesniper19

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Agree, it would take a bit of time to learn the skill of lapping a barrel with say a lead slug. Less risk is using a patch with a fine polish which is more or less polishing away copper/carbon fouling as well as slight removal of uneven spots. One needs to limit the amount of material removal... Important is also to know if the process is needed or not.

I have seen the lapping machines at cut barrel makers in Europe as well as the US it is not hobby gear. Was also very lucky to have worked with the guy who made the seals/ valves for your first moon landing air supply in the suits. Allowed was 1 litre of helium leakage in 30 years and this Swiss guy was chosen to make them. We needed the same or similar process for our ceramic seals.
edi
Agree - polishing and lapping are not the same. Removing copper through polishing is fine and hard to overdo unless you go bonkers with the process to the point that you change the dimensions of the barrel (its possible but **** thats a lot of work). Lapping significantly changes the inside dimensions of the barrel should be left to professionals.

What does making moon suits and ceramic seals have to do with lapping a barrel?
 

ejg

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What does making moon suits and ceramic seals have to do with lapping a barrel?
The lapping process, choosing the right abrasive materials, carrier liquids and getting a feel for the process. The "know how" needed to optimise just as in lapping a barrel.
edi
 

JMGamesniper19

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The lapping process, choosing the right abrasive materials, carrier liquids and getting a feel for the process. The "know how" needed to optimise just as in lapping a barrel.
edi
Yup I am going to be that guy

So you observing the process in a shop and then working with a "guy" who was part of the process in making an air valve in moon suit in 1966 is consistent with, gives you the ability to choose materials and abrasives, and the expertise to lap a barrel? The amount of leakage allowed in a valve has what to do with lapping a barrel? Furthermore, the nationality of the person chosen to do it means what to lapping a barrel?
 

ejg

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Yup I am going to be that guy

So you observing the process in a shop and then working with a "guy" who was part of the process in making an air valve in moon suit in 1966 is consistent with, gives you the ability to choose materials and abrasives, and the expertise to lap a barrel? The amount of leakage allowed in a valve has what to do with lapping a barrel? Furthermore, the nationality of the person chosen to do it means what to lapping a barrel?
Wow I better hold back with the chat on here,
The 12 Years of Engineering education on two continents including German mechanic trade helped with my know how in the lapping process, as well as 30 year toolmaking, moulding, and component manufacturing of which some needed a lapping process. Those that know lapping only from the barrel manufacturing process would have seen a fraction of what lapping is all about. That is why I refer to other processes in the industry that I came across. Just like bedding which I initially learnt in heavy machinery not with rifles. Exactly this broadening of the horizon was what lead NASA in those days to search worldwide to find experts in specialized industries. Hence finding the Swiss guy I mentioned.
BTW isn't improving the seal between barrel and bullet a reason for lapping? Even lapping a slight choke into the barrel?
edi
 

JMGamesniper19

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Wow I better hold back with the chat on here,
The 12 Years of Engineering education on two continents including German mechanic trade helped with my know how in the lapping process, as well as 30 year toolmaking, moulding, and component manufacturing of which some needed a lapping process. Those that know lapping only from the barrel manufacturing process would have seen a fraction of what lapping is all about. That is why I refer to other processes in the industry that I came across. Just like bedding which I initially learnt in heavy machinery not with rifles. Exactly this broadening of the horizon was what lead NASA in those days to search worldwide to find experts in specialized industries. Hence finding the Swiss guy I mentioned.
BTW isn't improving the seal between barrel and bullet a reason for lapping? Even lapping a slight choke into the barrel?
edi
Perhaps the 12 years of education would have had you focused on the original need and question. The question is "should I lap my barrel?" It wasn't "can anyone quote some 55 year old process by some person no one ever heard of that doesn't make rifles or rifle barrels so that I can understand if I need to lap my barrel"
Perhaps the education on 2 continents would have helped you to look at first principles of the question rather than following that up with "Look how cool my rifle is cause I lapped my barrel" through some process that I "observed"

Still haven't heard what all that engineering background has to do with helping BFD understand if he should lap his barrel. Guess you showing how cool your rifle is cause you lapped the barrel means everyone should stop what they are doing and start lapping their barrels? Everyone here with a sub 1/2 min rifle should take them apart and lap them cause they are all crap if we didn't?

Look. We are trying to help a guy with a question. Not talk about how smart we are or how cool our own rifles are. Toolmakers aren't automatically good at lapping barrels cause they make tools. No one is. Lapping is as much an art as it is a science. It takes time, effort and personal coaching if you dont want to mess up a few barrels along the way.
Bedding now? What does that have to do with lapping?

Ok I obviously get frustrated with folks who turn a question into something else so they can expound on how cool their stuff is. We are trying to help a guy figure out if he should lap his barrel. That is it.

Tapping out. Probably should.
 

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