Topic: Fire Lapping?... Chromelined barrel?

[RedRussell]

I am debating about replacing my barrel on my AR. I just can't get under 2" groups at 100yds. I switch and borrow my uncles rifle or my buddies and I shoot sub 1" so I know it isn't all me! lol. I was reading about Fire Lapping and thought it sounded like an ok thing that would be worth trying, if it messes my barrel up more I was going to replace it anyways! The barrel I have is a 16" YHM 1/9 twist chromelined with the scalloped fluting. Just so you all know what the starting platform is. The cost of getting the bullets and then you can load them your self is about $35 or you can order loaded rounds through Cabela's for about $40. I have read that loading them yourself is more reliable but costs a little more, big whoop.

I am wanting to know if anyone has tried this and what your results were and I also want to know that since I have a chrome lined barrel if it will just be a waste or tear the barrel up more and so on and so forth. Thanks!

[luvmy45]

What load are you shooting in your AR that's giving you bad groups? Handloads or factory? Grain of bullet?

How many rounds through the AR? how far to the throat? the spacing may be way off and the bullet jump causing issues? How is the crown on the barrell? any damage?

Sandpapering the barrel may do something for you, but if you have groups that big, I suspect that it's not just the barrell but there are other contributing factors.

[Jeff]

It's unlikely that the Tubbs2000 bullets will do much to improve a chrome lined barrel.  It probably won't hurt any though.

[J Mack]

I’m sure someone with more knowledge will be able to answer you fire lapping question, but maybe I can help with you barrel issue.
How many rounds have been fired through this barrel?
Did this barrel ever shoot well?
How do you clean the barrel and how often?
What grain bullet are you shooting and what different bullets have you tried, did it shoot one better than the others?
What optics are you using on this rifle and did you rule out any issues with it?

Chrome lined barrels are not known for the best accuracy and 2 MOA is not as bad as I’ve seen from them but my guess is that your barrel will not benefit from fire lapping if sub MOA is what your looking for.   

[RedRussell]

As for loads, if you open the book and flip to the .223 and the 5.56 section I have tried every load in my Speer book. Some are pretty good but others are terrible. I have found that 26grns of Varget and a 55 v-max are really good, we mass load that because it is the best for my uncles rifle. I shoot rough 2" groups with it. The crown on my barrel is great, no dents or dings, nice and clean. The barrel has roughly 3000-3500 rounds through it. I had to shoot my uncles Weapon in the Ironman this year because I couldn't get a good group. I don't know about how far it is to the throat. It is pretty much a factory YHM Specter rifle. Only mods have been furniture and sights pretty much. When I first got the rifle I shot a good 1" at 100yds, from a bench without bags.

I know chromelined aren't the best for shooting good groups but it is what came on the gun, I am looking at replacing it with a chromoly one from Bravo Company.

[RedRussell]

I have done opens(2 different ones) and a Pine Ridge Scope as well as a Mark AR 3x9 and a Nikon Monarch 3x9 on it just to make sure, I also have used 3 different scope mounts with all of them to make sure it wasn't the mount... Check on the optics being good... lol!

[J Mack]

My guess would be copper fouling.
Try cleaning with some aqueous ammonia until you are sure no copper could be left the barrel. Shoot five shots and clean again. See if it comes back to the 1MOA groups.
If you don’t have access to aqueous ammonia use a strong cleaner like the foamy stuff and don’t be afraid to let it sit or run it through several times until there is no sign of blue.

[fj40mojo]

RedRussell,
Have you tried thoroughly cleaning the bore with a good copper solvent. JMack has got the super secret sauce that takes out even the worst fouling if you don't have the patience to do it the old fashion way. Since you say that at one time it did shoot and now doesn't that is where I would start. Clean it down to bare metal. Patches at the muzzle that look as clean as when they went in the breach.  

[RedRussell]

lol you mean like my service rifle?! I did that and it still wasn't back to shooting as well as when I broke it in and everything. It did shoot better though. I have been using Hoppes No 9. Is that enough or should I use something stronger... If there is a solvent that I can get down here in Salt lake(I am at Ft. Douglas for my orders...boring!) that I could try I will run and grab it tomorrow. Where can I find that Aqua one?

[J Mack]

You need something stronger than Hoppes No 9.
Hoppes No 9 is gun oil compared to real copper remover.

FJ uses some foamie stuff and reports good success. 

[RedRussell]

Ok I will go and get some "good" stuff tomorrow. I will give it a really good scrub down and let you know in a day or 2. Thanks guys!

[J Mack]

Ok I will go and get some "good" stuff tomorrow. I will give it a really good scrub down and let you know in a day or 2. Thanks guys!

Remember if you can smell it it's not strong enough.
The stuff I use is like the old smelling salts and will knock you on your arse if you try to smell it.

[fj40mojo]

Aqueous ammonia is an industrial strength ammonia (the super secret sauce that JMacks got) and the active ingredient in Sweets 7.62 and other ammonia smelling copper solvents. It's popular among the .50BMG crowd. The foamy stuff (Outers foaming bore cleaner) is good at getting out powder fouling but I don't think it takes copper out like the Aqua stuff. Here's how I do it.

1. Fill the bore with Outers foaming bore cleaner and let it sit for an hour or so.
2. Dry patch the Outers out.
3. Run 3 sloppy wet Aqua stuff patches down the bore and let stand for 15-20 minutes.
4. Dry patch the Aqua stuff out.
5. Run 3 more wet Aqua patches down the bore and read for signs of remaining copper. If these patches don't come out clean I let the bore stand for another 15-20 minutes and repeat steps 3-5 until there is no sign (blue patches) of remaining copper.
6. Finish with a patch wet with Kroil.

[birddog1989]

Get a new barrel, put it on your rifle and don't look back.  Novak or Saber Defense. 

[Bill, Idaho]

Another sniper and I lapped a few of our SWAT sniper rifles.  Keep in mind, these were Remington PSS's, and did NOT have chrome bores. (I really don't think lapping will work on a chrome bore. If so, hardly at all.) The results were shall we say, interesting at best.
  We followed the instructions to the word. What we ended up with was marginally smaller groups, the clean-cold shot was marginally closer to where the group went, cleaning was noticeably faster,
BUT, each barrel we lapped wore out WAY sooner than the ones we didn't lap.  Think about it. Lapping is wearing out the barrel in a controlled manner. I realize for L.E. purposes, barrel life is probably not the primary concern with a bolt-gun, accuracy is. (Technically, when you get right down to it, cost is, but that's a whole 'nother topic). Is lapping worth it? I think it depends on what you gain compared to what you lose.
    But, in this case, there are some other variables that should be considered first.
    And remember, there are two types of bore cleaners. Fouling, which Hoppes, Shooter's Choice,etc, are for---and copper removal. Copper removal solvents will say they are specifically for just that. One will not work for the other. 

[XDMHMMWV]

From I have read, fire lapping won't do anything for a chromed lined barrel. The chroming lining is too hard.
Why not just sell it ( tell the person about the accuracy) and buy a chromoly barrel instead?

[RedRussell]

Ok, after about 2 hours of good cleaning the group has gotten better but not enough for my liking. I am down to 1.5" groups. Yeah I was talking to a smith from my unit and he said "lapping a chrome barrel is like waxing a 4x4 before you wash it, there is no point..." So new barrel it is. I would love to just drop something like a saber in it but money is something I have to watch, unlike some people. If it weren't I would have just done that to start with.

[birddog1989]

How about this one.  I'm making the assumption you want a 16" barrel.

http://www.midwayusa.com/viewProduct/?productNumber=627879

[RedRussell]

I have a 16" now and was going to go up to a 18" or a 18.5" barrel if I was going to invest the money. A little extra speed on the bullet and hopefully some better accuracy. For that price though I would stick with a 16" because for the most part it does it's job. Ok... what do you guys think about or know about this barrel?

[J Mack]

If I wanted a sub MOA barrel for my AR I would order another Krieger Barrel or a PacNor from Noveske.

I have some of each and they all shoot well, I had and sold some other brands that claimed sub MOA but fell short.   

[birddog1989]

Can't remember what Pac-Nor barrels go for but the other 2 are about 4-500 easy.  He said he didn't have that much to work with.  The reviews on the barrel on the link looked OK but only 2 of them so play your cards and take your chances.  DPMS and Model 1 Sales have decent barrels and a lot of profiles.

[Jeff]

I prefer Armalite barrels.  If you are OK with 1:9.  IMO, they have always been the best bang for the buck.

[carharttfarmer]

dpms 18inch rifle length gas system more velocity and should shoot slightly softer
http://www.midwayusa.com/viewProduct/?productNumber=431749

best all around i would have went with it if it was instock when i ordered mine ended up with there mini sass 18inch barrel it heavier and has a mid length