Barrels, which manufacturer??

[TwoMore]

The one with the correct twist rate would be better than the one with the incorrect twist rate.

not trying to be a bad guy in any way,but how did the rifle get built with the wrong twist in the first place, I have seen multiple posts about it, seems to me that if a part gets sent wrong it should be replaced before building. One good thing on this thread, check twist rate before putting it in the lathe. If I get sent a wrong crankshaft or piston I dont built with it. that would be a builder's "oops".

 

[Edd]

This is what Krieger has to say about break in.....

BREAK-IN & CLEANING:
With any premium barrel that has been finish lapped -- such as your Krieger Barrel --, the lay or direction of the finish is in the direction of the bullet travel, so fouling is minimal compared to a barrel with internal tooling marks. This is true of any properly finish-lapped barrel regardless of how it is rifled. If it is not finish-lapped, there will be reamer marks left in the bore that are directly across the direction of the bullet travel. This occurs even in a button-rifled barrel as the button cannot completely iron out these reamer marks.

Because the lay of the finish is in the direction of the bullet travel, very little is done to the bore during break-in, but the throat is another story. When your barrel is chambered, by necessity there are reamer marks left in the throat that are across the lands, i.e. across the direction of the bullet travel. In a new barrel they are very distinct; much like the teeth on a very fine file.

When the bullet is forced into the throat, copper dust is removed from the jacket material and released into the gas which at this temperature and pressure is actually a plasma. The copper dust is vaporized in this plasma and is carried down the barrel. As the gas expands and cools, the copper comes out of suspension and is deposited in the bore. This makes it appear as if the source of the fouling is the bore when it is actually for the most part the new throat.

If this copper is allowed to stay in the bore, and subsequent bullets and deposits are fired over it, copper which adheres well to itself, will build up quickly and may be difficult to remove later. So when we break in a barrel, our goal is to get the throat "polished without allowing copper to build up in the bore. This is the reasoning for the fire-one-shot-and-clean procedure.

Every barrel will vary slightly in how many rounds they take to break in For example a chrome moly barrel may take longer to break in than stainless steel because it is more abrasion resistant even though it is a similar hardness. Also chrome moly has a little more of an affinity for copper than stainless steel so it will usually show a little more color if you are using a chemical cleaner. Rim Fire barrels can take an extremely long time to break in, sometimes requiring several hundred rounds or more. But cleaning can be lengthened to every 25-50 rounds. The break-in procedure and the cleaning procedure are really the same except for the frequency. Remember the goal is to get or keep the barrel clean while breaking in the throat with bullets being fired over it.

Finally, the best way to tell if the barrel is broken in is to observe the patches; i.e. when the fouling is reduced. This is better than some set number of cycles of shoot and clean as many owners report practically no fouling after the first few shots, and more break-in would be pointless. Conversely, if more is required, a set number would not address that either. Besides, cleaning is not a completely benign procedure so it should be done carefully and no more than necessary.

 

[Pdvdh]

not trying to be a bad guy in any way,but how did the rifle get built with the wrong twist in the first place, I have seen multiple posts about it, seems to me that if a part gets sent wrong it should be replaced before building. One good thing on this thread, check twist rate before putting it in the lathe. If I get sent a wrong crankshaft or piston I don't built with it. that would be a builder's "oops".

The first and primary oops was the barrel manufacturer's failure to button rifle a 10-twist barrel.
Secondary oops is gunsmith doesn't measure twist rate prior to mating barrel to action.
Third oops is 3yrs after I've received rifle and I'm developing a load without success. Bullet requires a minimum 10-twist. I measure my twist rate multiple times over two full revolutions. 10.55 twist.
I ask gunsmith about barrel. He checks barrel order invoice and confirms 10 twist was ordered. Informs me that button rifling twist rates are not precisely controlled. Tolerances are less than cut rifled. Could be faster or slower than specified.
I research the subject and confirm that fact, although 5% error is beyond typical variation.
You ask HOW did this happen? I already stated smith did not verify twist rate prior to shipping me the completed rifle. Only the individual that rifled the barrel blank could possibly provide the answer to your question. Clearly the barrel manufacturer either didn't confirm the manufactured twist rate, or measured it and decided it was close enough, or thought the odds of anyone measuring the twist rate and making an issue about it were so low - he shipped the barrel to my gunsmith.

What makes one better than the other?

The barrel with the correct twist rate is the better one. Which rifling method provides the more accurate twist rate during manufacture? Cut-rifled.

What happens when your button rifled barrel is delivered with a twist rate 5% slower than the twist rate ordered? You're informed that button rifling of barrels is an imprecise method of controlling twist rate.

And then you're faced with the reality that it is what it is...

 

[Pdvdh]

If I get sent a wrong crankshaft or piston I don't build with it. That would be a builder's "oops".

If the crankshaft or piston manufacturer failed to produce a product matching what you ordered, they would be assigned the greater degree of fault by any court in this country.
If you caught the error before building with the faulty product, good for you.
Who's best equipped to perform quality control inspections? The product manufacturer, or the end user?
But I understand your point.
The finger can be pointed in different directions when assigning blame. However the product manufacturer bears primary responsibility, in my opinion.

 

[TwoMore]

If the crankshaft or piston manufacturer failed to produce a product matching what you ordered, they would be assigned the greater degree of fault by any court in this country.
If you caught the error before building with the faulty product, good for you.
Who's best equipped to perform quality control inspections. The product manufacturer, or the end user?
But I understand your point.
The finger can be pointed in different directions when assigning blame. However the product manufacturer bears primary responsibility, in my opinion.

I agree totally , just a bad situation all around I have to be honest, I (used to) rarely check twist

 

[bigngreen]

not trying to be a bad guy in any way,but how did the rifle get built with the wrong twist in the first place, I have seen multiple posts about it, seems to me that if a part gets sent wrong it should be replaced before building. One good thing on this thread, check twist rate before putting it in the lathe. If I get sent a wrong crankshaft or piston I dont built with it. that would be a builder's "oops".

The twist rate is built into the button but when it's pushed or pulled there is a lot of resistance obviously and as that resistance changes in the barrel the twist rate changes. Some will rotate the blank while buttoning to assist the button, others like X-Caliber use a hydraulic cylinder from the farm supply and just crash it through and hope for the best and they are the worst barrels I've seen for hitting actual twist rate.

This is how my day went with the last cheap barrels I tried to use, unpackage barrel, borescope, see poor lapping, which I can do if needed. Check with a reamer bushing and find my largest size falls half way through the barrel then sticks which means it's variable size bore, slug the bore and find it's a ***, call the company and get the run around and find out the twist rate is between the two buttons they have, finally get a replacement sent, call customer, package back up and send barrel back. Get new blank, repeat the entire process with the same results, call a barrel manufacture and get a barrel that is only $80 more then ship second blank back. This process and time means I paid money to chamber and fit a barrel for a customer, I like the guys I do work for so I don't charge them for all this but for me it's frustrating cause I'm trying to be in business not QC'ing someone else's!!
In contrast a Rock, Kreiger or Bartlein I unpackage the barrel and verify info on the blank is correct to the order, push a cleaning rod through it and load it in a lathe and dial it in, odds are good the reamer bushing is already the right one on the reamer so I don't have to surf my whole set, fit, chamber flip and crown and make a little money to try to afford more tooling or upgrade a machine.
Getting lucky with a barrel as a guy just buying one is awesome, you win, being a smith and get unlucky with one and your out money, I had one and it cost me $950 to get the customer back to where it should have been, that means I did 3 chamber jobs just to pay for that one $200 barrel that I stood behind! Hopefully that gives some insight into why some of us will use only certain barrels, when your ready to hang your lively hood, reputation and time on a barrel saving $100 on a chance doesn't even land on my radar!!

 

[TwoMore]

Hopefully that gives some insight into why some of us will use only certain barrels, when your ready to hang your lively hood, reputation and time on a barrel saving $100 on a chance doesn't even land on my radar!!

It sure does,that it a very respectable post! thanx

 

[tim_w]

The twist rate is built into the button but when it's pushed or pulled there is a lot of resistance obviously and as that resistance changes in the barrel the twist rate changes. Some will rotate the blank while buttoning to assist the button, others like X-Caliber use a hydraulic cylinder from the farm supply and just crash it through and hope for the best and they are the worst barrels I've seen for hitting actual twist rate.

Oh so true!!! It's also a great way to break buttons as well. I had a button I had made up destroyed by a barrel maker that will go unnamed from doing just that. A way to keep production speed up as well. Buttons are not quick to have made nor exactly cheap especially when it has very specific types of specs.

Biggreen, you are seriously a wealth of experience and knowledge and without knowing you, just by your posts, makes me think you are smith that has many happy customers; maybe even more so if some do not realize the grief you save them.