Gunsmithing Rough Barrel

downhill

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Jun 19, 2010
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Problem- 24"ss1/9 barrel free floated on AR. Group size at 200yds about 3 1/2 to 4 inches. Average of 5 different loads from 55 to 75 grain bullets.
Cause-Rough bore(really tears up a cleaning patch). As a side note the Bbl has less than 120 rds down it.
Question-Any simple solutions to remedy problem? (Did check for burr at gas port)
 

madd0c

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Re: Rough Barrel

Intersted to see what the smiths here will recommend. I wonder if firing some tubbs final finish bore lapping bullets through it might clear up the roughness.

madd0c
 

nashlaw

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Re: Rough Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: madd0c</div><div class="ubbcode-body">Intersted to see what the smiths here will recommend. I wonder if firing some tubbs final finish bore lapping bullets through it might clear up the roughness.

madd0c </div></div>

If it is tearing up the patches, the barrel is too far gone for the Tubbs. I have used the product with good results on some pretty bad barrels with decent results, but this is too far gone. This is my opinion from past experience.
 

crumpett

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Re: Rough Barrel

If the barrel only has 120 rds through it, how can it be "too far gone". I would shoot some firelapping rounds through it,shoot them like you were shooting a group. I'd bet it will show improvement.
 

nashlaw

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Re: Rough Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LordofPangea</div><div class="ubbcode-body">If the barrel only has 120 rds through it, how can it be "too far gone". I would shoot some firelapping rounds through it,shoot them like you were shooting a group. I'd bet it will show improvement. </div></div>

I was not referring to the round count. The "too far gone" reference was in regard to the condition of the tube- tearing up patches. Rounds are not the only thing that eat up a barrel. Where I live, humidity has ruined many deer rifles that Bubba had kept in the closet and not swabbed with a good oil. I have firelapped some factory barrels that were a bit sour, but if the bore is as rough as the original poster says, it may be time to rebarrel.

def: too far gone(descriptive phrase): not dead, but breathing heavy
 

crumpett

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Re: Rough Barrel

Certainly a lot cheaper to put a few lapping rounds through it. I have seen that improve some pitted barrels. What have you got to lose?.
 

bohem

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Re: Rough Barrel

How old is this barrel that it has under 120 rounds through it, tears up a patch, and doesn't have a burr at the gas block? Was it left in the closet without any preventative maintenance on it like Nashlaw suggested?

If the upper is new and it's been doing this since the beginning I would call the manufacturer and complain that you've had a hell of a time getting it to shoot. After 120 rounds you're done screwing with it and you would like them to take a look.

If it's a 10 year old upper that was left to roll around in a truck bed for the past 119 months then you're SOL and it might just be time for a new barrel.

EDIT: I did have an LR260 upper that would not shoot worth a damn and it tore up patches. Once the crown was repaired it turned back into a 1/2" shooter @ 100yd. I'm doubtful it's the crown, but stranger things have happened.