Skidding on revolver bullets, variable or constant?

[Changeling]

For those who have experienced skidding on 44/45/50 calibers by recovering and checking the bullets, question?

Did the width of the skidding appear constantly the same width from front of bullet to rear or did it change width, get wider/narower from one end or the other as best you could tell?

[felix]

Width is not constant. Does not have to be. We need a computerized (extremely fast) camera that takes pictures of boolits rotationally and as well as horizontally to compute the ratio of the spin compared to that of desired. ... felix

[mellonhead]

I have had bullet skid on both my 475's and my 500. In all cases it started to skid but quit till it got to the last band. In all case I had good accuracy also.

Toby

[Wolfer]

IMO if you have skid to the base you will have gas cutting. I believe you always have skid on the front band but the rear should mirror the rifling.

[44man]

Skid will be wider at the front and MUST stop at the base. It does no harm.
If your marks are even full length it means you have no skid at all.

[subsonic]

Has anyone done a test to see what contributes to skidding besides alloy?

[44man]

Fast powder is worse because of where it peaks. Many think low pressure loads do less damage but the boolit gets an instant thump.
It is still mostly alloy and why the GC came to be, softer lead was used back then.

[1500FPS]

Has anyone done a test to see what contributes to skidding besides alloy?

You have a bullet that is traveling forward with no spin out of the cylinder. Then it hits the forcing cone guiding it into the bore (hopefully the cylinder alignment is spot on and the bullet is pretty well centered with the bore) and it hits the rifling. Now the rifling has to get a grip on the bullet to start rotating it. That doesn't happen instantly. Thus you see the skidding until the rifling fully grips the bullet. The harder the bullet the less skid.

[subsonic]

I guess what I'm asking is what affect does distance to the rifling have on it? Powder burn speed? Primer selection? Boolit shape? Rifling configuration? etc?

[1500FPS]

I guess what I'm asking is what affect does distance to the rifling have on it? Powder burn speed? Primer selection? Boolit shape? Rifling configuration? etc?

The longer the time it takes the bullet to hit the rifling the more speed it has gained making it harder for the rifling to grip the bullet. More skid.

[subsonic]

But has it been proven? Or is that theory?

Is it the PRESSURE that makes it strip, or is it the SPEED that it hits the rifling? Or is it the weight of the projectile that has to be spun up?

3 scenarios:

BFR long cylinder .500S&W with a big jump to the rifling:

Heavy 650gr long nose boolit that is close to the rifling.

Light 350gr "wadcutter" type boolit with a long jump.

Medium 450gr boolit with a middling jump to the rifling.

Which one has the best chance of not skidding assuming all 3 are plain base, same alloy, and similar velocities and powder burn speeds?

[1500FPS]

But has it been proven? Or is that theory?

Is it the PRESSURE that makes it strip, or is it the SPEED that it hits the rifling? Or is it the weight of the projectile that has to be spun up?

3 scenarios:

BFR long cylinder .500S&W with a big jump to the rifling:

Heavy 650gr long nose boolit that is close to the rifling.

Light 350gr "wadcutter" type boolit with a long jump.

Medium 450gr boolit with a middling jump to the rifling.

Which one has the best chance of not skidding assuming all 3 are plain base, same alloy, and similar velocities and powder burn speeds?

If you are driving down a highway that has a concrete barrier wall along side it and for some terrible reason you drive your car into that wall at a very shallow angle it starts grinding itself on the wall plus the engine has quit which is going to take the wall longer stop your car, if you were car was doing 30mph or if it was doing 65mph? Get the idea now? It's the momentum of the bullet, in addition to the gas pushing it, that control how long it takes the rifling to get a good grip on it. Previously I told you that harder the bullet it the sooner the skid will stop.

[subsonic]

Have you tested it?

[1500FPS]

No I haven't tried plowing my car into a concrete wall ! :kidding: It's a known fact among revolver shooters. You can even see a slight skidding with jacketed bullets. Another factor that will let the bullet skid more is shallower rifling.

[44man]

I never worried about boolit jump to the rifling like the distance in my BFR 45-70. I never want any boolit at the end of a cylinder. I have shot 50-50 boolits from the BFR, oven hardened but found they must have a GC. I normally shoot WD, WW boolits. It has not been a problem at all.
Just toughen enough to control where skid ends.
Rifling has not mattered, the BFR's all have fast twists and are the most accurate revolvers I ever shot and I use PB in all of them.
Many things do change skid like boolit weight and powders but all can be controlled with the alloy.
Some say pure or soft lead to 700 fps with fast powders. So take a look to see you have 14,000 to 16,000 cup right now on the boolit. How many pounds can you hit a boolit with using a hammer? Put a boolit on the vise and just hit it easy yet thousands of pounds in the chamber must be different. You turn the boolit to a ball of putty and expect it to spin!!!!
Remember the tests I did with Unique and 231 in the .44 with a 245 gr Keith style? I did not get accuracy until I got to 28 and 30 BHN. If I was shooting .38 wad cutters I would be shooting darn hard lead.

[Changeling]

Thanks Jim, I understand completely now. I wanted this information in regard to the development of my bullet.

Thanks to all for there input.

[44man]

A friend was over with his .41 last week and his boolits were long, right at the cylinder end. He shot a few times and the gun locked up. A boolit had pulled just a few thousandths so I had to tap it back in with a dowel. They looked like they had good case tension and enough crimp but the gun is light and he does not hold as tight as I do so that can be a factor.
I have seen a SRH in .454 lock up using over crimped factory cast loads.
The worst are revolvers with short cylinders so if you need a few shots for a bear attack, you can be toast. Out in the field hunting and having one pull will end your hunt that day unless you have some tools.
Soft lead can pull easier then harder. WD, WW metal has worked for me in the .475 and JRH, never had one move, same in the .454, even in a Freedom. Lube too slippery is no good.
It is just not a good idea to make OAL to the end of the cylinder. I have never seen any loss in accuracy. If I remember my .45-70 boolit has to move almost 9/16" to the gap. Most accurate revolver I ever shot. I shoot eight different boolits from it and a few have shot 1/4" groups at 50 yards.
My .475 boolit does not have a long nose and will fit a Freedom and still have some room. That is the boolit I hit 4 out of 5 (first shot a sighter) on the 6" swinger at 400 yards.
To ease your mind, it is an old wives tale that jump must be reduced. Falls into the bump up to obturate category.

[littlejack]

44:
With what you are saying about bullet jump, and what others find about other things that go wrong in someone else's gun but
not theirs, leads me to believe that this hole fiasco of handgun loading and shooting is a crapshoot. What works for one persons
firearm, may not/will not work for another. That leaves a person who has a problem firearm, (leading, bad accuracy etc.) to try
all remedies known and hope for the best outcome.
Jack

[subsonic]

Or you could put it another way.

If the same load shoots great in one gun and leads up the other, is the problem the load or the gun?

[littlejack]

exactly.

[44man]

Or you could put it another way.

If the same load shoots great in one gun and leads up the other, is the problem the load or the gun?
I would say it is the load. In the .44 alone, my loads shoot the same from every .44 they have ever been stuck in, I have owned 9 myself. Not to say a gun can't have a problem, it happens but seems to be not as common as is stated. My friends own many of the calibers I have from the .44 to the .500's and everyone uses my loads. Most come here to cast or they bring me lead and I cast for them.
Scott bought a new SBH Hunter, I did the trigger, put an Ultra Dot on it and he sighted it at 50 yards. Every single group was 1/2", better then my old SBH.
I just have never seen a gun needing different.

[frank505]

My 32 twist 45 Colt barrel shows no skidding and is accurate with 360 grain keith style slugs at ridiculous ranges.

[littlejack]

That's no fair, that is a different animal.

[1500FPS]

It's both.