Banded bullets for especially larger calibre bullets in this case

Flint

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My respectful comment. Your respectful opinion please.


Multiple/more than two pressed grooves AKA crimping grooves on a bullet refer.

With a bullet/s, e.g. a jacketed 500gr 458/350 gr 375, encased in lead, and the likes in mind.
And for the speed and comparative cheapness in manufacturing. For that matter perhaps in a mono metal bullet as well.
But especially the solid. For my question/idea could adversely affect the performance of an expanding bullet. Although can the following suggestion still be engineered into the suggested design.


In stead of only one crimping groove, can the originally placed grove for crimping, and more be pressed into bullets.
My reasoning is that with less barrel contact, could the barrel-to-bullet friction be quite a bit less and bullet speed, for those who require this, be increased, with, and for my requirement, a lighter amount of report to one’s shoulder. At least for me who do not appreciate excessive recoil.



A second comment is that these additional crimped grooves need to be very shallow. Only say 12 or 14 thou in order to only be free of the rifling. And not necessarily impede on bullet strength.



I’m not into the physics side of the matter.



Thank you for your participation.
 
Are you familiar with the North Fork bore rider design?
Though they are mono copper , only a fraction of the shank actually contacts the barrel metal.
I have used them for several years and just loaded and tested some of the 350SS bullets in my 45-70 double and am very pleased with the performance.
Here is a link to the .458 350 and one to the overview site page:
.458 350 link https://www.northforkbullets.com/458-350.htm
All NF bullets link https://www.northforkbullets.com/bullets.htm
 

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Please do not over do any crimping effort - You are more likely to break your die than dent the bullet.
 
Thanks CRS.
Will research.

Actually meant that the additional crimping should be done during bullet manufacture.
 
Actually meant the additional grooving should be done during bullet manufacturing.
 
Doesn't Barnes already do what you are suggesting?
 
Thanks for your comment Shootist43.

Not certain at all.
I know that mono meta/lathe turned bullets have multiple recessed grooves.
But will further research whether lead filled solid capped bullets have this feature.

If there's a way to do it better..... find it. Thomas A Edison.
 
Mono metal bullets will have multiple 'grooves' because early designs that copied conventional bullets created high pressure as the bullet didn't conform to the rifling very easily. Modern designs have the grooves so that only a small amount of copper or brass needs to be engraved with the rifling and that bit of copper can be moved into the space created by the groove.

Conventional (lead encased in a jacket) engrave more easily because they are a bit softer. Creating grooves in the jacket would weaken the jacket and would require an extra manufacturing step making them more expensive. Kind of a solution to a problem that never existed. You can experiment with a crimping groove tool. I think Lee make one. Make lots of crimping grooves in a solid-I suspect the lead core will begin to squeeze out.

I really don't think you want to be making the conventional solids more likely to deform and weakening them further. Varmint rounds might benefit but not solids for DG.
 
Thank you Nhoro!

Yes. The overriding concern was the jacket being weakened.
And your comment that the engraving is easier with the lead core being forgiven is truly valid.
Also must the bullet manufacturers have walked most every avenue.
Appreciated.

"Nhoro" rang a way gone bell. A bell from 1975. I had it. But yet did'nt. But the internet reminded me. Greater Kudu. In Shona.
Homesickness for Rhodesia!
God bless!
 

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Thank you Gerard.

Will have a look at this.
 
I believe the "groove" you refer to is actually called a cannelure. An additional cannelure can indeed be pressed into conventional jacketed bullets even after manufacturing. A tool for this purpose is sold by C-H Company in the USA. Hand loaders typically use the C-H tool to roll a cannelure in jacketed bullets meant for rifles which require crimped bullets while loading bullets not originally intended for that use. I suspect a C-H rolled cannelure would marginally improve bullet core-jacket integrity, without extruding core material significantly or otherwise disturbing the bullet too much. But how much it may help prevent core/jacket separation is a matter of debate and experimentation. And whether it would actually reduce pressure/recoil or improve velocity would also need to be tested.
 

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