Rifle no longer chambers factory ammo

NitwiT said:
Hi Southcountryguy, I understand what you are saying, the problem lies in that without a borescope or otherway of gauging this, I may have already removed the carbon build up, as everything but Hornady factory loads easily.

Not sure on the accuracy range of the calipers, but they seem accurate enough to reliably sort out a .005 inch difference. If they were rounding, the 0.2644 should have rounded down to 0.264.

Not sure where you found the mentioned pressure signs. The only thing I ran into was being unable to close the bolt on Hornady, then Barnes factory ammo. Handloads fed and shoot very well. After cleaning, Barnes factory now loads, but Hornady does not. Just asking in case I missed a pressure sign, but I always check my primers, case heads, necks, etc for indications of danger, and have yet to see anything except a sticky bolt lift when finding what my max load in this setup was.
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I think you will find that most callipers are "accurate" within 0.001" - find the box or the papers that the thing came with - is likely that is what the maker says, if it is not actually written on the tool itself. Is typical that a common micrometer says it is "accurate" to 0.0001" - so, that is 10 times more accurate than a calliper, if they are checked and verified on a standard - is typical that a Mitutoyo micrometer (used to) comes with an ASTM certified standard in the box - I am not aware of any brand of calliper that comes with one. Most machinists will tell you that most users can measure with a calliper within about 0.005" of the "true" value - "user error" in the amount of tension, square-ness, etc.

I found it gets more complicated to measure the diameter on a cylinder - like a bullet - because you are also concerned about how "round" it is - so there are potentially hundreds of diameters on that same cylinder to measure - to see if they are the same or not. And I found it is very difficult to get back to precisely the same diameter to repeat a measurement a couple times to verify my numbers.

Do not confuse a readout as "accuracy" - I notice at least a couple made-in-China callipers that I bought from NAPA store, they say on their box they are "accurate within 0.001", although they have a display that shows to four decimals. I am sure most can realize that if an object has a "true" dimension of .0230", and if the calliper is "accurate within 0.001", and if the user is "perfect" with it - no user error - that display will read any number from 0.022" to 0.024" and will be "within 0.001" of the true value. I suspect you are fooling yourself to think you will measure to 0.0001" accuracy, with a hand held calliper.

If I followed your post above (#36), you are proposing to distinguish between bullets with diameter of 0.2644" and 0.2645"? Can be done, but I do not own the tooling, nor do I have the measuring skill to do that. And no maker will make a product to that precision - especially a product sold in bulk or quantity greater than about one - what will be produced and sold to a customer will have a "plus/minus" tolerance - so +/- 0.01"(?) +/- 0.001"(?) or perhaps +/- 0.0001"(?) from nominal.
 
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All signs point to a carbon buildup in throat and possibly neck in chamber. My PRC did similar (throat) but at 500-600fps faster

Get a carbon remover. And a borescope.
As mentioned, Soak a patch, push thru, soak another patch and let sit in the throat overnight. Or plug barrel and fill with carbon remover.
Then I would (and do) use a brush and spin it in the throat - a good 15-25 turns. Then patches again.
My bet would be that you are good to go. Get a borescope.

Myself, I use Carb-out, as well as Automotive carb cleaner. And I use a blue iosso brush. I did use a bronze brush for this too, both worked good. But after the bronze brush cleaned it 100% after a neglected heavy buildup, I now just use the blue brush, and clean it much more often - no issues, and way better consistency with groups.
I also use a case length gauge to trim brass to the precise chambers length, not the length that the "book" says - this helps reduce carbon a lot.

Spend $80 and get a borescope.

Don't overthink it - then once you get it done, keep your chamber and throat clean - consider doing it when barrel is still warm after a session..

And MAKE SURE you remove any oil from the chamber.
 
with all that cleaning it might be worth reestablishing your col with the dummy round idea, just for your base line again

has been interesting followng this, but am still uncertain how a carbon ring that limits the brass going into chamber would cause a bullet to seat so hard as to pull out of the brass
2 issues maybe?
remember col dummy rounds are individual for each individual bullet
 
Hi Boxhitch, just to clarify, the brass was not being prevented from chambering, the bullet was jamming in the throat due to excess something in the there. And yeah, with the ring cleaned out, pressures SHOULD be different, so I may have to start from scratch on load development again :)
 
I had no idea a rifle could get that much buildup, will be watching closer now
are you getting clean patches yet? That Sweets has ammonia in iirc? can be too corrosive so be careful
 
Remember,
Sweets is for copper, not carbon. Copper specific. Make sure to rinse Sweets out.

Heavy baked on throat carbon is best removed with a specific carbon remover and a brush.

You can still get clean patches with heavy carbon buildup - it can be baked on, impervious to many cleaning agents.
Again, Carbon on a patch is grey/black, copper is blue/green.

Look at it this way - a combo 'carbon and copper' remover (pick brand) is like using all season tires on a truck in winter
Specific copper or specific carbon removers are like using winter tires in winter.

Now having said that, some combo cleaners are pretty good - I have used Butches and boretech eliminator and followed their instructions, and they do work good. Boretech instructions use a wire brush, and worked the best for me of all the combo cleaners that I have tried.
But copper or carbon specific cleaners work real real good.

There is no doubt carbon build up is a royal PITA, so best to stay on top of it.

I don't have the privileges to post pics here anymore, but I took many borescope pics of all we are discussing here - its real easy to see the progress with what works (and what doesn't)

The two PRC barrels I have used both get carbon and copper buildup heavy just beyond the throat for 8ish" and about the same copper buildup near the muzzle. Nature of the beast.
 
NitwiT said:
Hi Southcountryguy, I understand what you are saying, the problem lies in that without a borescope or otherway of gauging this, I may have already removed the carbon build up, as everything but Hornady factory loads easily.

Not sure on the accuracy range of the calipers, but they seem accurate enough to reliably sort out a .005 inch difference. If they were rounding, the 0.2644 should have rounded down to 0.264.

Not sure where you found the mentioned pressure signs. The only thing I ran into was being unable to close the bolt on Hornady, then Barnes factory ammo. Handloads fed and shoot very well. After cleaning, Barnes factory now loads, but Hornady does not. Just asking in case I missed a pressure sign, but I always check my primers, case heads, necks, etc for indications of danger, and have yet to see anything except a sticky bolt lift when finding what my max load in this setup was.
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A hard closing or opening bolt is an indicator of possible pressure issues.

Most calipers have an accuracy tolerance of + or - 0.001” although they may read like they are more accurate. A reading of 0.263 or 0.265 on a 0.264 bullet is within the accuracy of your calipers.

If you have all the carbon out and you cannot chamber factory rounds either the barrel or bullets are out of spec neither likely but possible. Chances are due to the shape of the hornady bullets they are making contact where the others aren’t. You could test this by painting the bullet with a jiffy or smoking it chambering it and seeing what marks are given. Also could seat the other bullets out farther and see if they do the same.

As mentioned use a carbon cleaner for carbon and don’t be hung up on the fact a product isn’t marketed for firearms. Your automotive parts store will have good cleaners for carbon.

Good luck.
 
Barnes may seat their bullets deeper (they like jump), hence them not contacting the carbon ring, therefore easy to close bolt.
The marks on the Hornady bullet on previous posts are screaming carbon ring contact. This will cause hard bolt closure
Measure CBTO and you'll see if there is a difference
 
NitwiT said:
As the title implies, I own a rifle, and have owned this rifle for several months. The rifle is a Christensen Arms Mesa, in 6.5 Creedmoor. I have been working up a load for hunting and target shooting, and round count is now sitting at 250 or so.

In the course of this, I had dialed in the rifle to shoot Barnes Factory LRX, and went through a couple boxes playing around with them. I shot handloads in between to continue trying to find a happy medium between accuracy and speed. Having failed that, I settled on a nearly minimum charge varget load, shooting 3/4" or so, at 2500ish fps.

Now, seeing that my rifle likes slower rounds, I decided to try the Hornady ELDX's, (although I love my Barnes). I can't get them to chamber, the bolt will close most of the way, but won't turn down. There appears to be rubbing marks on the brass jacket.

I found this strange, so I went to a 1/4 box of Barnes factory I had left. These won't chamber anymore either. Back to my handloads, and noticing that the bolt closes, however, feels stiff in the final portion of closing.

I've visually (eyeball) inspected the action, bolt, bore, barrel, and all seems well. No noticible discoloring or particles. The ejector and plunger on the bolt appear to be working as they should.

I did try a bit more effort then I should have on one Barnes factory, resulting in the bullet being pulled from the brass upon extraction. This seems to say that the issue is in the throat? (not sure on the term here).

Looking for some ideas on what I can do to solve this

Mark
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Not the first time I have heard of a rifle not being able to chamber factory Hornady ammo.
one day we had two different rifles that would not chamber 6.5Creedmoor Hornady, and another would not chamber their 308 ammo, but would chamber Federal.
Cat
 
So... for those watching, I manned up and bought a bore scope. Video is of the scope inserted from muzzle end of rifle and pushed back to the chamber.. yuck. Lots more cleaning to do.

Hope this works. I have some heavier cleaning chemicals on route, but surprisingly short of the good stuff in most shops.
Boretech Eliminator is going to have a go.
 
You need to stop. Get rid of the sweets. ASAP. Buy Wipe-Out tactical advantage and Wipe-Out patch out. Also buy a possum hollow bore guide, a few IOSSO blue brushes and IOSSO bore paste. Get a Bore Tech coated rod of the correct bore size along with the complimentary jag.

When that all arrives wet several loose fitting patches with the tactical advantage and let that bore soak for 24 hours. Then wet a brush with the same solvent and brush that thing back and forth 20 times. Push the crap out with patches and check it. If that doesn’t get it all repeat. But this time use the Patch out. If that doesn’t do it put Iosso paste on your brush and go after it 20 times again.
 
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Hi Pathfinder,

thanks for the input. I have a carbon fibre rod, as well as the correct sizes jags, patches, nylon and bronze brushes, as well as a bore guide and bore mops. I have Wipe-Out tactical advantage, wipe-out patch out, and wipe-out accelerator on the way. The Bore Tech eliminator will get here first and I'll give that a try.

Im curious as to the "get rid of the sweets'. What I had read online was that it was decent for this application.
 
Wipeout is good stuff. I like the foaming kind. Easy to use but it takes time. Possum hollow boreguides are also good. Get the optional solvent port
 
NitwiT said:
Hi Pathfinder,

thanks for the input. I have a carbon fibre rod, as well as the correct sizes jags, patches, nylon and bronze brushes, as well as a bore guide and bore mops. I have Wipe-Out tactical advantage, wipe-out patch out, and wipe-out accelerator on the way. The Bore Tech eliminator will get here first and I'll give that a try.

Im curious as to the "get rid of the sweets'. What I had read online was that it was decent for this application.
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It will damage your bore, does zero for carbon and there is no need for it. Use Wipe-Out.
 
yikes!
Well at least you can see what you are up against! If it were me, i would follow Boretech eliminator instructions - patch/soak it and then use a wire brush. Repeat. Agree that Iosso may be needed too (i would wrap a size smaller brush (6mm) with a BE soaked patch and glob of Iosso, then short stroke it the first 8").

I am sure you will have to do the process a few times, as that is quite a knarly buildup!
Good luck!

Post another vid as you progress
 
Have two rifles the chambers sucked and a brass brush for a larger caliber with a short piece of gun cleaner rod in a cordless drill with Hoppes cured the problem.
 
pathfinder76 said:
It will damage your bore, does zero for carbon and there is no need for it. Use Wipe-Out.
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Sweets will not and does not damage the bore.

With chrome moly barrels it will clean the bore and leave it susceptible to rusting if you do not finish by patching with oil. That's the only way any damage may occur... the rusting...

You can soak metal in sweets as long as you like, it will not 'eat' metal. It will not damage bluing.

Back in the late 60's early 70's it was extremely common to use Sweets 7.62 cleaner for cleaning the copper and powder fouling and JB Bore Cleaning Paste occasionally for any carbon buildup... Even back then some people thought Sweets damaged metal... not understanding it left metal so clean it was susceptible to rusting...
 
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