Barrels

[TonyL]

Hey peeps,

As many of you will know, I often look in on the Pyramydairblog by Tom Gaylord. You can very often find interesting information on there and it's a pretty good resource to have a good browse through.

Looking at his report of May 14 on the Benjamin Fortitude Gen II, it seems that Crosman have recently poured much attention towards their barrels and I found the following making interesting reading.......

"Crosman learned that reaming the seamless hydraulic tubing they use to make barrels (a very common practice in the airgun industry today) before rifling improves the consistency of the inside of the barrel. The firearms industry has known this for years and there is ongoing discussion whether hammer-forged barrels or reamed, button-rifled barrels are better. That's because hammer-forging does leave the barrel with slight differences in interior diameter that can sometimes be felt by pushing a wire brush through the bore. Both types of barrel are quite accurate and only when you get down to the gnat's eyelash is there any difference to report."

All quite interesting reading methinks. And well worth a read of the whole article (if only I could do links

[buttloaves]

https://www.pyramydair.com/blog/2020...-rifle-part-1/
There you go, interesting read.

[TonyL]

Thank you.

[Craig-P]

Hold onto the thought of barrels, Tone - I’ve got a project nearing completion that you may find interesting

[john79]

Hold onto the thought of barrels, Tone - I’ve got a project nearing completion that you may find interesting

looking forward to this Craig

[TonyL]

Hold onto the thought of barrels, Tone - I’ve got a project nearing completion that you may find interesting

I'm waiting, I'm waiting, I'm waiting.........is it done yet, Craig?

Will look forward to seeing that, Craigy.

[severnsider]

Hi Tony,
It would seem to me that if using tubing (rather than deep-hole boring solid bar stock) reaming would be an obvious requirement regardless of the method of rifling used. BSA are (were?) well known for the quality of their hammer-forged barrels, but they weren't made from tube to start with were they?
The manufacturing processes are thus quite different - nowhere near as critical for a weedy air rifle than for a decent full-bore rifle, but Crosman may have just admitted that their crappy manufacturing methods are not as good good as they ought to be. After all, would Ducati make steel bore liners from "tube" or would they be properly cast/forged to ensure uniform structure then machined to the correct size?
Hope you're well Sir and that you've recovered from your recent affliction!

[TonyL]

Hi Mike,

Yes, doing well, thank you. And I hope you're keeping well too?

Yep, BSA barrels always seemed to be held in high esteem. There used to be a video on their website showing some of the barrel making techniques. Don't know if it's still on there?

[TonyL]

Aha, just watched that video again from the BSA site. Excellent.

Whilst on the you tube thing I spotted a few more videos on BSA Guns. One in particular that I've just watched, showing the history of BSA even features our Terry. It's called "BSA Guns, made in Britain".

Sorry, I'm a 'puter numpty and can't do links, but it's well worth a look.

And sorry to ping off at a tangent.

[evert]

.......

"Crosman learned that reaming the seamless hydraulic tubing they use to make barrels (a very common practice in the airgun industry today) before rifling improves the consistency of the inside of the barrel. The firearms industry has known this for years ......"

Which basically means that Crosman found out that they had gone TOO cheap in their manufacturing methods.
That reaming mass produced hydraulic tubing is necessary before rifling shouldn't surprise anyone who has a basic knowledge of guns and metalworking.

[greenwayjames]

Hi Tony,
It would seem to me that if using tubing (rather than deep-hole boring solid bar stock) reaming would be an obvious requirement regardless of the method of rifling used. BSA are (were?) well known for the quality of their hammer-forged barrels, but they weren't made from tube to start with were they?
The manufacturing processes are thus quite different - nowhere near as critical for a weedy air rifle than for a decent full-bore rifle, but Crosman may have just admitted that their crappy manufacturing methods are not as good good as they ought to be. After all, would Ducati make steel bore liners from "tube" or would they be properly cast/forged to ensure uniform structure then machined to the correct size?
Hope you're well Sir and that you've recovered from your recent affliction!

The tubing used is precision bore tubing which is made to extremely close internal dimensional tolerances and is an entirely different animal when compared with hydraulic tube. You get what you pay for in this life. Perhaps, who knows, Crosman think its more economical to buy in a less expensive raw material item and ream. All air rifles barrels up to and including the early Meteors were cut rifled the same as the centrefires and even they started to switch to hammer forged before their eventual downfall.

[Shed tuner]

Which basically means that Crosman found out that they had gone TOO cheap in their manufacturing methods.
That reaming mass produced hydraulic tubing is necessary before rifling shouldn't surprise anyone who has a basic knowledge of guns and metalworking.

indeed... seamlees tube is pretty good uniformity, to allow a o-rings to seal in a hydraulic application... but the uniformity reqs for gun barrel bores are a little more precise !