Hi I was just wondering if you have a 38 super Tanfoglio pistol, sorry I only have 2 S&W revolvers, when I first got the gun I was told to use 9mm projectiles not 38/357 ones? I have found that using 9mm 125 grain projectiles for major loads, they tumbled, at minor loads they were fine and now since using the 124 grain conical frontiers (copper coated) in minor loads they work but are not very accurate. I recently bought 125 grain 38 SWC hard coated lead and with a minor load are very accurate. The question I have is should I use the 38/357 projectiles instead of the 9mm as the pistol is a 38 super? The polygonal barrel that is in this pistol has the smooth rifling and I think needs the 38/357 size projectiles for a tighter fit, and if so will this extra size do any damage to the barrel????
Thanks for any help you can give me.

Marke

With the .38/.357 lead SWCs I can't imagine you will do any harm. However, historically caution has always been indicated when using lead in polygonal barrels. I would be very careful to keep an eye open for lead accumulation. I'd be much more concerned with that than the extra thousandth or two of diameter. JMHO.

its a worthy concern however, most data from the past several years in poly barrels has shown coatings negate the issue.
but, I have not personally tested this to any extent that I would like. Tell us what you think after about 1500 rounds or so.

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it just needs more voltage

I reload 9mm, 38Super and 38Spl and have found that when using hard cast lead projectiles, I get the best accuracy from all of them by using .357dia. cast bullets. I would assume that coated bullets would act the same. I don't have any experience with guns having polygonal rifling though and understand that many guns rifled in this way can fowl quickly. YMMV

You might try some Hi Tek coated lead bullets in your 38 Super and see how they shoot. Bayou Bullets makes some nice Hi Tek coated bullets in .356 (9mm & 38 Super) and .358 (38/357) that are otherwise the same bullets except for sizing. I would get a hundred of each to see what your pistol prefers. And like M29since14 said, polygonal rifling and cast lead bullets generally are susceptible to leading. But the coating on these bullets should alleviate this from happening. I've had great results with Bayou Bullets in the past and tried to get their bullets to lead in my 357 and 44 revolvers and couldn't get them to lead the barrel, even with very hot loads. Now if you live in a country outside of the US, I guess you would just have to find a local source for your Hi Tek coated bullets.

Out of curiosity, what Tangfolio pistol do you have that has polygonal rifling?

I own many 38 Supers including two Tangfolio Witness pistols and all have traditional lands and grooves for the rifling. I just looked at seven Witnesses and none of the ones I have on hand are polygon rifled.

To the question, with true jacketed projectiles they should all work fine. With lead, thin plated lead and coated lead projectiles that will all obturate more easily, generally speaking, .357s or .358s will work better than .355s or .356s. The only way to know for sure what the minimum lead projectile diameter for your firearm is would require that you slug the barrel.

I have never had a problem with lead in any polygonal barrels. I only recall those warnings starting when Glocks came on the market. Since I won't own a Glock, it is a non-issue for me.

38 Super

Can't comment on the poly rifling aspect. I load .355, .356, and .357 diameter bullets with excellent results from my 1911 platform.

I do have an undersized sizing die. With most brass I have it's necessary for a more secure fit when using the .355's.

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GOA
USA Shooting Supporter

I had accuracy problems with 9mm plated bullets in a couple of .38 Super 1911s. Went to jacketed bullets and got my accuracy back. Not sure what the problem was but suspect the .38 Super was driving the plated bullets a little too hard.

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Cliff
CCSO, FPD ret, USN ret.

One bullet maker of coated lead bullets for the 9mm stated that the .357 dia. gave the best accuracy in a lot of weapons.

A jacket 9mm bullet is standard at .355"

A lead 38 starts out at .358 dia. and can go either way.

The wear and tear and dia. of your barrel might not be "Stock".
If you have it "Slugged" it might help you get or find better accuracy.