Flat base vs Bevel base

[crsides]

I last reloaded in limited quantity 30 yrs ago. All the cast bullets we bought then was flat based, SWC. I read that alot of bbl erosion and leading in magnums (357, 41, 44) was from bullets that did not fit the bore (001+) and bevel based bullets that allowed hot gases to get by the base. Most of the commerical cast bullets I am looking at are bevel based.

What is the scoop on Bevel based bullets?

Can you recommend a flat based bullet commercially for top end mag loads in 357 (27-2), 41, and 44. Looking for Keith type, SWC bullets in all three.

thanks

Charlie

 

[Titegroups]

If you look around enough you can find kieth style bullets for sale, automated casting machines release "Blob" bullets much easier so that's what youll find for sale for the most part. I cast my own sharp edged keiths. There's many schools of thought on bevel bases and everybody is sure their opinion is right. I agree they go in the cases a little easier.

 

[Steve C]

I read that alot of bbl erosion and leading in magnums (357, 41, 44) was from bullets that did not fit the bore (001+) and bevel based bullets that allowed hot gases to get by the base.

I think you are mixing up LEADING with erosion and the things you list causes leading in revolver barrels. Erosion is caused by the blow torch effect of powder gasses and solids striking the barrel. Erosion is found in rifles and rarely in handguns as the powder used in handguns is a lot faster and of smaller amount. If you are seeing barrel erosion in your handgun its due to your powder selection and not your bullet.

If you are pushing the bullet hard you will generally produce pressures that bump up the base to fill the bore even with bevel base bullets. How much pressure you need will depend upon the hardness of the bullet.

Personally I don't use a bare base lead cast bullet for any top end load and if loading hot with slow powder I use jacketed or gas checked.

 

[mikld]

Actually, gun barrels will last much longer shooting cast bullets. Bevel based bullets were designed to drop from the mold easier with the advantage of being inserted into the case easier than flat base. As you mentioned, leading is caused by hot gasses getting past the base of the bullet and depositin melted lead in the barrel. Bevel based bullets don't seal the bore as good as flat based bullets and allow easier leading the barrel. Most commercial cast bullets are too hard and many too small and it's a good idea to measure, with a micrometer, any bullets you buy just to make sure what size they really are. Fit is key to shooting cast lead bullets so you gotta know the dimensions of your gun (slug the barrel to find groove diameter and slug the cylinder throats). Good fitting lead bullets can reach magnum velocities without leading; I've shot slightly over max loads of True Blue under a 358" cast SWC, wheel weight alloy, in my Taurus 357 Mag. with no leading and often shoot 245 gr SWC plain base in my .44 Magnums at over 1200 fps with no leading.).

I cast, but when I want some bullets that I don't have a mold for I buy from Beartooth Bullets Beartooth Bullets > Home. Beartooth makes sever different diameters for each caliber so you can buy bullets that will fit your gun (they supply .357" bullets from .356" to .358" and some rifle .357" bullets to .360").

 

[358156hp]

Bevel based bullets are much easier for automated casting machine to cast bullets with fully filled out bases, and the bevel helps protect the base from shipping and handling damage. However,in some shooting disciplines like bullseye shooting, some competitors don't resize their cases at all, preferring to leave the case at it's fired dimensions for greater consistency in chambering and chamber alignment. Often, the shooter will simple bell the case mouth slightly and seat their bullet (commonly a bevel based wad cutter), which is also unsized, and of a slightly oversized diameter. This way the brass is worked less than normal, and the finished cartridge is really pretty consistent dimension wise. A slight taper crimp finishes everything off.

 

[fltbed]

Generally speaking, if the bullet diameter is correct for the bore, and the bullet hardness is correct for the pressures your loading to, and the lube is up to snuff, bullet base will have little effect on accuracy, leading or wear.

I’ve only run across one revolver that would not shoot bevel base bullets well. It’s truly the exception rather than the rule.

That said, for velocities over 1200 f.p.s. I’ve had better results from gas checked or jacketed bullets.

Jeff

 

[ArchAngelCD]

If I were getting leading in my barrels I would look at several other causes before I turned to the bevel base of the bullet.

 

[Robert Palermo]

Bevel vs Plain Base

The common misconception that bevel based bullets were developed for easier automatic casting has been a misnomer for as long as I have been in the business. Bevel base bullets were developed for use for commercial loaders to make loading cartridges easier.

Automatic casting machine molds can be made plain or bevel and makes no difference in the casting process.

Molds that were hand cast molds and then adapted for automatic use gave problems when such designs were not made for such use and had nothing to do with the base design.

The accuracy issue should be laid to rest as bevel based bullets are just as accurate or even more accurate than their plain base counterparts if all the other design parameters are good such as driving band length and nose profile and weight balance to the design.

A properly designed bullet with low weight deviations fitted to the gun will yield the best results for accuracy.

 

[amazingflapjack]

mikld-thanks for the link-looks like nice stuff.

 

[4barrel]

I DO NOT like slugs .001 over unless they are 38 hbwcs 750 fps & under. I like flat base wad cutters-- swcs-- all pistol calibers-- but u have to make them yourself if u wont to go faster--Its like hot rodding--If you push it faster one thing aint gona work. Stick with your original thinking. I shoot any speed I like up the max with wheel weights & 15% lino. Casting aint that hard & no lead problems. SKIP has the prettiest boolits.

 

[ChuckS1]

I don't like bevel base cast bullets only because it makes a mess when I run them through my lubesizer. There are some bullseye shooters that will tell you that a flat base bullet is more accurate at 50 yards than a bevel base one, but I can't shoot well enough at 50 yards to tell the difference.