Bullet Keyholing - Page 1

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Posted: 5/30/2018 12:45:59 PM EDT

Bullet Keyholing any suggestions to remedy, greatly appreciated? Rifle was shooting great but then, I'm in California and had to go featureless. Removed flash hider and replaced with Comp. This is when keyholing started, then removed comp but keyholing still occurs. Ammo is good Federal factory .223 55 gr., barrel is 1/7" from Delton, have less < 4,500 rounds through barrel.

Posted: 5/30/2018 1:33:47 PM EDT

[#1]

Your seeing keyholes no matter if you use the flash hider, the comp, or bare muzzle?

Check your crown to see if you dinged it while swapping flash hiders and comps? If so, you can get your muzzle recrowned. If the crown is good, you may have just shot out that barrel. Have a smith look at it with a good bore scope.

Posted: 5/30/2018 5:57:59 PM EDT

[#2]

I suspect your barrel is shot out. Is the barrel chrome lined, nitrided or is it one of cheap phosphate barrels Delton puts out?

You could mess up your crown pretty bad and not get key holing...https://rifleshooter.com/2018/03/do-rifle-crowns-matter-does-a-crown-effect-accuracy/

Posted: 5/30/2018 6:08:28 PM EDT

[#3]

It's either shot or dirty as fuck

Posted: 5/31/2018 7:18:47 AM EDT

[#4]

Sounds like the crown was effected during remove/replace of muzzle device...

Posted: 5/31/2018 5:32:11 PM EDT

[#5]

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Quoted:
Sounds like the crown was effected during remove/replace of muzzle device...

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That could result in a POI shift or open the groups up a bit, but not likely to result in key holing.

This "crown"...

Shot these groups:

Posted: 6/1/2018 5:07:32 PM EDT

[#6]

While the crown can play a part in accuracy, it's not really going to impact the keyhole issue. With that number of rounds through it and if not kept clean, the barrel could be shot out. The keyholing, is the result of the projectile not being stabilized, that's where the rifling comes into play. Have a smith take a look at the barrel, might be time to do a barrel swap.

Posted: 6/1/2018 8:08:09 PM EDT

[#7]

Quote History

Quoted:
While the crown can play a part in accuracy, it's not really going to impact the keyhole issue. With that number of rounds through it and if not kept clean, the barrel could be shot out. The keyholing, is the result of the projectile not being stabilized, that's where the rifling comes into play. Have a smith take a look at the barrel, might be time to do a barrel swap.

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Most of my students wig out when they start producing keyholes. When I ask them how they clean it they usually reply something along the lines of Hoppe's 9

The vast majority don't even know there are very different and specific solvents for both powder and copper

And then they freak out again because their cleaning patches come out bright blue

Posted: 6/2/2018 1:38:54 AM EDT

[#8]

Well, crap. How should a barrel be cleaned, then? Asking for a friend. :-)

Posted: 6/2/2018 11:16:15 AM EDT

[#9]

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Quoted:
Well, crap. How should a barrel be cleaned, then? Asking for a friend. :-)

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brush and swab the barrel with your favorite powder solvent until the patches come out to your desired level of cleanliness

after that, do the same with copper solvent

when you're done, go shoot it again. or store it. you do you.

Posted: 6/2/2018 11:21:44 AM EDT

[#10]

looks like .22 through a .30

Posted: 6/15/2018 5:31:17 PM EDT

[#11]

Needs Butches Bore Shine or Barnes CR-10. Both are copper solvents. Use with bronze brush. Protect muzzle. Soak and scrub vigorously, but don't let these copper solvents sit longer than about 10 minutes. Clean until patches are no longer blue/green. These solvents and bronze bore brushes will not harm the barrel as long as you don't mess up the muzzle. Finish up with Hoppes #9 and then follow with dry patches.

Then do a few fouling shots. If it is still keyholing , the barrel rifling is shot and it needs a new barrel.

Posted: 6/22/2018 9:22:47 AM EDT

[#12]

You only need to clean copper when accuracy degrades. That is usually around 500 to 1500 rounds, depending on your acceptable level of accuracy. If you only shoot 50-250 rounds, no need to clean copper, IMO.

Posted: 6/22/2018 10:07:36 AM EDT

[#13]

@jrent

any follow-up?

Posted: 6/22/2018 10:21:00 AM EDT

[#14]

Quote History

Quoted:
I suspect your barrel is shot out. Is the barrel chrome lined, nitrided or is it one of cheap phosphate barrels Delton puts out?

You could mess up your crown pretty bad and not get key holing...https://rifleshooter.com/2018/03/do-rifle-crowns-matter-does-a-crown-effect-accuracy/

View Quote

Thanks for posting this, very interesting and contrary to what has always been drilled in my head.

Posted: 6/26/2018 4:17:05 PM EDT

[#15]

Thanks for the suggestions had a gunsmith inspect couldn't find any visible problems. Got some Hoppes Copper Solvent, left in the bore overnight in an attempt to get it clean. Realized I had <5k rounds through it but never tried to get the copper out. I'll report back after I've shot it. Hopefully it was just poor maintenance on my part!

Posted: 6/28/2018 2:34:08 PM EDT

[#16]

Quote History

Quoted:
Thanks for the suggestions had a gunsmith inspect couldn't find any visible problems. Got some Hoppes Copper Solvent, left in the bore overnight in an attempt to get it clean. Realized I had <5k rounds through it but never tried to get the copper out. I'll report back after I've shot it. Hopefully it was just poor maintenance on my part!

View Quote

I hope you did not irreparably etch/corrode the barrel bore by leaving that stuff in over night. I don't know about the Hoppes Copper Solvent, but the good stuff, Barnes CR-10 and Butch's Bore Shine, (also Sweet's) have a huge amount of ammonia in them. It's the ammonia that works on the copper.

They are very effective but can do harm if left longer than about 10 minutes or so at a time. Scrub, soak up to 10 minutes, run patches, repeat until patches are no longer blue/green. But soaking more than 10 minutes might not be advisable. I hope it worked, though.

Let us know if you solved the keyholing.

Posted: 6/28/2018 3:13:34 PM EDT

[#17]

Thanks for the concern but Hoppes says OK to leave overnight. I had read about the others mentioned but decided to give Hoppes a try with less ammonia concentrate first to see if it solves the problem.

Posted: 6/28/2018 3:45:59 PM EDT

[#18]

Quote History

Quoted:

I hope you did not irreparably etch/corrode the barrel bore by leaving that stuff in over night. I don't know about the Hoppes Copper Solvent, but the good stuff, Barnes CR-10 and Butch's Bore Shine, (also Sweet's) have a huge amount of ammonia in them. It's the ammonia that works on the copper.

They are very effective but can do harm if left longer than about 10 minutes or so at a time. Scrub, soak up to 10 minutes, run patches, repeat until patches are no longer blue/green. But soaking more than 10 minutes might not be advisable. I hope it worked, though.

Let us know if you solved the keyholing.

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Hoppe's isn't anywhere near as aggressive as Butch's or Sweet's, if it's a chrome-lined barrel, I'd say have a blast at a couple of days rest in the bore

Sweet's in a 416R barrel? Fuck. That.

If you want to compare them, just open one and take a good sniff, then the other. You'll understand after that.

Posted: 8/4/2018 11:03:53 AM EDT

[#19]

@jrent any conclusion so far?

Posted: 8/4/2018 1:27:15 PM EDT

[#20]

I would not be the least bit surprised if a Delton barrel is shot out at 5K.

Posted: 8/6/2018 11:47:31 AM EDT

[#21]

Quote History

Quoted:
I would not be the least bit surprised if a Delton barrel is shot out at 5K.

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Dang @MILSPEC556 that ain't good to hear.

I have 2,500 rounds down an HBAR 1:9 Del-ton 20 inch barrel. Does this mean she will go south soon (or at 5K)?

I see that Battlefield Vegas group got some mileage out of the barrel. Hoping that I can get the same performance. not really planning extra budget for additional barrel in 2019 for that build.

Per Ron Henderson "High Round count thread:

"We haven't lost any bolts in our 20" guns and that includes one that just went down for "keyholing". I believe I purchased the barrel from Del-Ton about five years ago and it more than served it's purpose.

V/R
Ron "

Posted: 8/6/2018 4:23:11 PM EDT

[#22]

Quote History

Quoted:
Dang @MILSPEC556 that ain't good to hear.

I have 2,500 rounds down an HBAR 1:9 Del-ton 20 inch barrel. Does this mean she will go south soon (or at 5K)?

I see that Battlefield Vegas group got some mileage out of the barrel. Hoping that I can get the same performance. not really planning extra budget for additional barrel in 2019 for that build.

Per Ron Henderson "High Round count thread:

"We haven't lost any bolts in our 20" guns and that includes one that just went down for "keyholing". I believe I purchased the barrel from Del-Ton about five years ago and it more than served it's purpose.

V/R
Ron "

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Quoted:

Quoted:
I would not be the least bit surprised if a Delton barrel is shot out at 5K.

Dang @MILSPEC556 that ain't good to hear.

I have 2,500 rounds down an HBAR 1:9 Del-ton 20 inch barrel. Does this mean she will go south soon (or at 5K)?

I see that Battlefield Vegas group got some mileage out of the barrel. Hoping that I can get the same performance. not really planning extra budget for additional barrel in 2019 for that build.

Per Ron Henderson "High Round count thread:

"We haven't lost any bolts in our 20" guns and that includes one that just went down for "keyholing". I believe I purchased the barrel from Del-Ton about five years ago and it more than served it's purpose.

V/R
Ron "

I can't tell you for sure but what I can tell you is they are very much a budget company. Barrel life will depend on a few factors such as who made it and how, firing schedule (high heat kills barrels a lot faster) as well as what ammo you be been firing through it. A steel cased round with a bimetal bullet will wear said barrel out quicker than quality ammunition. Mag dumps will wear said barrel quicker than slow accurate fire. Just depends. But as far as the keyholing barrel you have, its probably done.

Posted: 8/8/2018 7:34:28 PM EDT

[#23]

In my experience key holing starts when the bullet goes sub sonic in it's trajectory.

Posted: 8/9/2018 11:58:52 AM EDT

[#24]

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Quoted:
In my experience key holing starts when the bullet goes sub sonic in it's trajectory.

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keyhole impacts occur whenever instability causes nutation

Posted: 8/9/2018 12:35:18 PM EDT

[#25]

Quote History

Quoted:
Thanks for the suggestions had a gunsmith inspect couldn't find any visible problems. Got some Hoppes Copper Solvent, left in the bore overnight in an attempt to get it clean. Realized I had <5k rounds through it but never tried to get the copper out. I'll report back after I've shot it. Hopefully it was just poor maintenance on my part!

View Quote

I shoot a lot. I don't use any copper solvent and really don't do much cleaning. A bore brush rarely touches my barrel. When it rains and I can't get out, I will clean. Usually swab with Mpro-7 and follow with CLP.

If I saw keyholing with factory ammo, I would immediately get a new barrel. Barrels are cheap in these salad days. Best bet is to get another rifle, and then another barrel.

Posted: 8/9/2018 1:16:55 PM EDT

[#26]

Quote History

Quoted:

I shoot a lot. I don't use any copper solvent and really don't do much cleaning. A bore brush rarely touches my barrel. When it rains and I can't get out, I will clean. Usually swab with Mpro-7 and follow with CLP.

If I saw keyholing with factory ammo, I would immediately get a new barrel. Barrels are cheap in these salad days. Best bet is to get another rifle, and then another barrel.

View Quote

Would agree to what @BBQ WHISPERER is stating here as barrels are indeed very affordable.

Have run a couple of the DTI without any troubles and they have grouped as well right along with the BCM gov't profile barrels and the PSA barrels for rack grade.

However with the turning out of rack grade barrels there is bound to be a few oinkers to land in the hands of consumers. Had one from one of the boards favorite "go to" locations.

To me if OP barrel has gone south in such short notice its a process error and he got a lemon. If I am DTI, I would RMA that barrel test it and give him a replacement.

If the latest DTI goes south within this year I'll replace with a Stealth or Criterion barrel as good quality barrels are affordable to joe six pack

Posted: 8/9/2018 1:38:00 PM EDT

[#27]

I have a Adams Arms 5.45x39 upper that has random fits of keyholing. Cleaning seems to solve it for a while. Has less than 2K rounds through it. It didn't do this when new, afraid to run suppressor on it now.

Posted: 10/23/2018 7:23:53 PM EDT

[#28]

Quote History

Quoted:

I shoot a lot. I don't use any copper solvent and really don't do much cleaning. A bore brush rarely touches my barrel. When it rains and I can't get out, I will clean. Usually swab with Mpro-7 and follow with CLP.

If I saw keyholing with factory ammo, I would immediately get a new barrel. Barrels are cheap in these salad days. Best bet is to get another rifle, and then another barrel.

View Quote

The original Mpro7 cleaner was awesome. It worked well in neutralizing corrosive salts left behind by corrosive ammo. I thought it also had some effect on copper fouling.

Sweets 7.62 does wonders on old surplus rifle bores. My brother cleaned his Mausers to the point no more residue would appear on a patch, then we applied Sweets and watched as the blue-green patches appeared.

Posted: 10/24/2018 4:23:45 PM EDT

[#29]

Quote History

Quoted:
I would not be the least bit surprised if a Delton barrel is shot out at 5K.

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+1

My comment isn't from experience with shooting out a Delton barrel (in fact I've never shot out an AR barrel). They're from my experience with the company's products in general.

They're lower on the quality spectrum than DPMS ....

Many people cite 6,000rds for a Colt M4 in US military service. Granted, those gun see combat conditions and full auto fire ... but I can 100% assure you a 4150 CMV chrome lined Colt barrel is miles ahead of anything Delton has ever made.

Posted: 10/24/2018 8:31:20 PM EDT

[#30]

From the Henderson Defense thread here:

" I had barrels from before we even opened the range with 1,000's of rounds on them from J&T Distributing (chrome-lined) that didn't keyhole well into the 80,000-100,000 range."

Posted: 10/25/2018 3:34:00 PM EDT

[#31]

Quote History

Quoted:

+1

My comment isn't from experience with shooting out a Delton barrel (in fact I've never shot out an AR barrel). They're from my experience with the company's products in general.

They're lower on the quality spectrum than DPMS ....

Many people cite 6,000rds for a Colt M4 in US military service. Granted, those gun see combat conditions and full auto fire ... but I can 100% assure you a 4150 CMV chrome lined Colt barrel is miles ahead of anything Delton has ever made.

View Quote

My experience (for what its worth)
Ive never seen a MIL barrel regardless of semi or full auto fire not make it to at least 10,000rds.
I have seen most quality civilian purchased Chrome lined barrels make it to 15,000 before any issues.

If a barrel starts crapping out under 8,000 (that's with rapid fire and fast shooting) since firing rate and amount work in tandem
to reduce barrel life. Then its a sub-quality barrel.
Really crappy:
I have seen low brand barrel marked chrome lined go out anywhere from 1,000 to 5,000 rounds.

My 2cents..If your rifle is key holing very good chance barrel shot out. Or if its shooting a 6in group at 25 yards, then its also shot out.

Posted: 10/31/2018 5:18:03 PM EDT

[#32]

Quote History

Quoted:
keyhole impacts occur whenever instability causes nutation

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Quoted:

Quoted:
In my experience key holing starts when the bullet goes sub sonic in it's trajectory.

keyhole impacts occur whenever instability causes nutation

Yes, and lots of potential causes. A common one not direcly applicable here, is twist too slow for the bullet shape/length. Like trying to shoot long 77 grain SMK bullets from a 1:12 twist or even 1:9. Going subsonic is not likely the cause here, either, although it will destabilize some bullets more than others. Nor is hypervelocity, such as causing a jacket to shed and destabilize the bullet. That's from super high rpm rotational forces on thin jackets. I've had that happen with very light varmint bullets with thin jackets fired at well over 4,000 fps from much more powerful rounds than .223. If the bullet hits the target at all, it is sideways. Often, they completely blow up and never even strike. Obviously not applicable here.

My bet is that either the bore is shot or the rifling is so filled with copper and carbon that the bullet may not be getting enough bite from the rifling to rotate it enough to stabilize it. Either would cause keyholing. The former can't be fixed short of a new barrel. The latter might recover after the copper and carbon layers are stripped away.

Posted: 1/20/2019 1:14:48 PM EDT

[#33]

Quote History

Quoted:
I have a Adams Arms 5.45x39 upper that has random fits of keyholing. Cleaning seems to solve it for a while. Has less than 2K rounds through it. It didn't do this when new, afraid to run suppressor on it now.

View Quote

Be sure to check your bullet diameter. I have read of issues with 5.45x39 ammo and lack of diameter QC.

Posted: 1/21/2019 10:38:00 AM EDT

[#34]

How did you remove/install the fs/mb? Tools?

[ARCHIVED THREAD] - Bullet Keyholing

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