Chamber dimensions to allow not cleaning

[Article 4]

Do you have any data on cleanliness vs precision you can share? How dirty before precision starts to slip? What are your recommendations for frequency of cleaning?

You wanna fund a study to solve your first question? If you do, ill run it....heck we can run it together with Frank.

To your 2nd question - I just shared that mil spec data last night in this thread.
If you are looking for an exact round count as a measure, you are likely not going to find that. Too many variables unless you set up a study to show exactly that - and it would have to be a huge sample set costing $$$$$$$ and have testing and mesuring devices built and calibrated for exactly that outcome. More $$$$$$$

For all the guys that don't clean, same question right back at you....do you have any measurable data? Have you done ANY comparison testing - havent seen any and when experts in the field, bbl makers, ballisiticians, and rifle makers provide deep experiential and Mil Spec data, you still wanna disregard it cause you and a few other people have had success not cleaning a bbl or 3

If yours aint broke, then dont fix it. Dont wanna clean, don't. Want validation for not cleaning? Not going to come from experienced bbl makers and industry leaders.

 

[Harvey_NW]

For all the guys that don't clean, same question right back at you....do you have any measurable data? Have you done ANY comparison testing - havent seen any and when experts in the field, bbl makers, ballisiticians, and rifle makers provide deep experiential and Mil Spec data, you still wanna disregard it cause you and a few other people have had success not cleaning a bbl or 3

See page 1 posts #19/20. I'd like to see the same empirical evidence from the experts, not just a story about how it was fixed by cleaning it.

 

[ljalberta]

Some fellows are awful lucky. I used to be a clean after every use sort of guy.

I’ll see how lucky I am. I’m not cleaning bores unless I see accuracy degradation.

My round count isn’t nearly as big as some, but I’m going to do Forms recommendation and shoot a 30 round group with a .223, 6CM, 6.5CM, and .308 and save to compare against in the future.

.223 will probably get 1,500-2,500 rounds on it this year. The others will likely be 100-500 each so it might be a long game test.

 

[Frank Green]

You wanna fund a study to solve your first question? If you do, ill run it....heck we can run it together with Frank.

I'll supply the barrel!

 

[Frank Green]

Here is what we are doing for the 7/6.5PRC round. It's not Saami and everyone involved that I listed is doing it all out of they're own pockets.... load data from different guys etc... is all over the place and no one and I mean no one has done any actual pressure data testing. So there isn't even a baseline to start with.

I won't even guess as to what this is all costing.




We are making a ammunition pressure test barrel (P&V) in 7/6.5PRC. Barrel finish length is 32". 5R rifling and 1-8.25 twist.

Hornady donated brass and 166/190gr ATIPs.
Sierra donated 183 and 197 matchkings.
Berger donated 180 Hybrids and some N555 powder.

The above was all donated at n/c.

I have some 180ELDM's and H4350 powder for loading as well along with H4831sc. I'll be doing all the loading and supplying all the lot numbers for the powder, primers, and bullets etc...

The barrel needs chamber work and pressure port work done still. Should be done early this month.

Hornady will be doing all the pressure and velocity testing.

This way we will get some good hard baseline data for pressures and velocities.

Hornady is doing all the pressure and velocity testing at n/c as well. I have to make a minimum of 10 loaded rounds per load. In some cases for the more popular stuff I'll be doing more.

As soon as the barrel gets done and shipped and I'll ship the ammo separately and Hornady can get the testing scheduled will have data.

Later, Frank
Bartlein Barrels

 

[Harvey_NW]

I'll supply the barrel!

If you're serious about that, I'll send you my address. I have enough 6 Creedmoor components to shoot a couple thousand rounds. Let's outline some criteria, and I'll document everything.

 

[TaperPin]

*chuckle*
No matter if a barrel test went 2000 rounds or 200, the cleaners will clean and the anti cleaners won’t.

 

[Article 4]

If you're serious about that, I'll send you my address. I have enough 6 Creedmoor components to shoot a couple thousand rounds. Let's outline some criteria, and I'll document everything.

One bbl we already have. Opinions we already have. We also have mil spec data that is already supplied and a part of this thread. 12 bbls set up identically as measured / reviewed and verified results.

Ok. Let’s up our game.
If we want to do this right, We need barrels. Like 30. Two sets of 15 each where all bbls must be as close to exactly the same as possible. Components for all, as close to exact and identical. We also need objective criteria, measuring devices, and objective reporting criteria aligned with agree to hypothesis. We need an impartial panel to read out the data and report on whether it is significant enough to support the hypothesis. Wanna do science, lets do science!!!

 

[Shortschaf]

See page 1 posts #19/20. I'd like to see the same empirical evidence from the experts, not just a story about how it was fixed by cleaning it.

To clarify, this is exactly what empirical evidence is, and there is no better evidence

 

[Harvey_NW]

To clarify, this is exactly what empirical evidence is, and there is no better evidence

Empirical is synonymous with verifiable, which is how I used it in context. Poor word choice, let's go with physical evidence.

 

[wind gypsy]

I like that this discussion is growing legs. Would love to see what something a little overbore, say 6 creedmoor, does without cleaning compared to cleaning over say 1000 rounds.

How many barrels would we need to get relevant outcomes? 2 cleaned barrels and 2 uncleaned? 4 total?

2 different powders?

 

[Frank Green]

One bbl we already have. Opinions we already have. We also have mil spec data that is already supplied and a part of this thread. 12 bbls set up identically as measured / reviewed and verified results.

Ok. Let’s up our game.
If we want to do this right, We need barrels. Like 30. Two sets of 15 each where all bbls must be as close to exactly the same as possible. Components for all, as close to exact and identical. We also need objective criteria, measuring devices, and objective reporting criteria aligned with agree to hypothesis. We need an impartial panel to read out the data and report on whether it is significant enough to support the hypothesis. Wanna do science, lets do science!!!

That's what I always say.... your going to do a test... you have to do qty. because one barrel etc... might not tell you anything conclusive.

When guys get into it with me on why claims by this or that barrel maker last longer than another brand... I say this....

You need 10 barrels at least from each maker.
They need to be made to the same specs for bore and groove sizes and rifling etc...
They need to come out of the same lot of steel.
Same chamber reamer needs to be used and if more than one reamer they need to be made to the same spec.
Then all the same lot of ammo/components need to be run thru them in controlled conditions.
Same cleaning cycles and cleaning equipment needs to be used.

You change just one thing of the above.... and you just screwed up the data/test.

That's the only way you will get a scientific answer.

Yes I have data from bullet/ammo makers for me to draw good data on barrel life by method the barrel was made etc... that's the best data I/we have access to.

As @Article 4 said....that's the right way to do it.

 

[Flyjunky]

This conversation has been had so many times on this forum.

As usual, blanket statements to clean or not clean are both wrong. The individual gun will tell you when/if it’s needed.

As the OP stated on the first page I had a gun built that I took possession of in June of ‘23. By this April it will be getting a new barrel already, I’ve shot it a ton. I can absolutely, positively, tell you that once I get around 80 rounds down the tube I’ll start seeing pressure and velocity increases by about 30-40fps. Happens just like clock work. Other rifles in my safe don’t have that problem.

Cliff notes to these 5 pages…every gun is different and the gun will tell you what needs to be done if you pay attention to it.

 

[HighUintas]

Yep. My goal is to see if I can make it work in my rifle while meeting my needs. Maybe I'll find that I just need to adjust my load charge after a couple hundred without cleaning. Or maybe I'll find I need a larger diameter throat.

Or maybe I'll just be pissing up a rope.

Worst case, I get to get a new barrel sooner, make my wife angry, and support Frank's barrel business

 

[Harvey_NW]

As the OP stated on the first page I had a gun built that I took possession of in June of ‘23. By this April it will be getting a new barrel already, I’ve shot it a ton. I can absolutely, positively, tell you that once I get around 80 rounds down the tube I’ll start seeing pressure and velocity increases by about 30-40fps. Happens just like clock work. Other rifles in my safe don’t have that problem.

Have you tried dropping the charge weight 1gr and continuing shooting?

 

[Flyjunky]

Have you tried dropping the charge weight 1gr and continuing shooting?

I’m about .7gr below pressure right now. This rifle has a tight chamber, with being over bore it’s just an inevitable factor but I don’t mind cleaning. I usually pour a whiskey, turn on some tunes, and tinker around while cleaning. For me it’s a therapeutic process. To each their own.

 

[Frank Green]

I’m about .7gr below pressure right now. This rifle has a tight chamber, with being over bore it’s just an inevitable factor but I don’t mind cleaning. I usually pour a whiskey, turn on some tunes, and tinker around while cleaning. For me it’s a therapeutic process. To each their own.

What do you mean by a tight chamber?

Tight/short throat spec?
A tight neck that makes you neck turn the brass?
A tight case body back at the .200" line from the bolt face?

Just curious and why I'm asking.

If you have a tight case body.... that will make bolt opening a problem but how much smaller did you have this area cut?

If a tight neck chamber but you are neck turning your brass for proper clearance... that shouldn't do anything then.

Throat spec.. possibly.

 

[ElPollo]

I’m enjoying this discussion. I can’t help but think that I’d enjoy being a fly on the wall when @Frank Green and @Article 4 got together with @Formidilosus to look at and shoot his dirty, beat up guns and figure out why he is getting the result he describes with the pile of barrels he lists.

 

[Article 4]

What do you mean by a tight chamber?

Tight/short throat spec?
A tight neck that makes you neck turn the brass?
A tight case body back at the .200" line from the bolt face?

Just curious and why I'm asking.

If you have a tight case body.... that will make bolt opening a problem but how much smaller did you have this area cut?

If a tight neck chamber but you are neck turning your brass for proper clearance... that shouldn't do anything then.

Throat spec..

What do you mean by a tight chamber?

Tight/short throat spec?
A tight neck that makes you neck turn the brass?
A tight case body back at the .200" line from the bolt face?

Just curious and why I'm asking.

If you have a tight case body.... that will make bolt opening a problem but how much smaller did you have this area cut?

If a tight neck chamber but you are neck turning your brass for proper clearance... that shouldn't do anything then.

Throat spec.. possibly.

Agree Frank - I primarily utilize SAAMI spec chambers unless the customer expressly asks for something different. If they do, I have a conversation with them around the purpose of having a custom reamer made. If they handload, what components they intend to use, etc....

This matters in this discussion as it pertains to cleaning. "Tighter" chamber fitment, throat fouling, freebore, and cleaning are all affected.
If the chamber is "tighter" than SAAMI and the shooter does not take the proper brass prep and loading actions, there can be issues. In a custom or "SAAMI minus" chamber, the build up of carbon and fouling can have a pronounced negative affect in feeding, pressure, freebore and bullet jump. More carbon in the chamber and throat, the more issues can present over time.

 

[Flyjunky]

What do you mean by a tight chamber?

Tight/short throat spec?
A tight neck that makes you neck turn the brass?
A tight case body back at the .200" line from the bolt face?

Just curious and why I'm asking.

If you have a tight case body.... that will make bolt opening a problem but how much smaller did you have this area cut?

If a tight neck chamber but you are neck turning your brass for proper clearance... that shouldn't do anything then.

Throat spec.. possibly.

I had a 6.5-284 built in which I wanted to use lapua brass and 156’s. When I was talking to my smith we had discussed reamers, dimensions, etc and he thought his reamer was CIP spec but come to find out it was Winchester spec. Which means not only was the chamber smaller at the rear of the chamber (.200) but it also had smaller neck clearance. So, after getting earlier pressure signs than I should have we revisited the reamer specs and found the above problem. Originally we just went in and opened up the back of the chamber to .502 which obviously allowed my case to expand further and decrease the pressure. Later on I turned my necks down as well because the lapua brass has thick necks for this chamber.

As a side note, even though all components (all same lot as before neck turning) were the same after turning the necks I dropped 53fps. It could be a couple different things with release of the bullet, more room in the neck area, etc but I went up .6gr and am back to my original speed.

Anyway, back to the question. Since doing all that I’m hoping the carbon ring and pressure around 80 shots will improve.

My point being, if you have a setup that has factors which are sensitive to carbon buildup the not cleaning mantra may pose problems.

Btw- it’s the most accurate gun I’ve ever had.