Guns and their projectiles are closely matched items.

What if the bullet is in the pocket of the shooter and is thus warm and
the gun is outside and at a fairly cold temperature of zero Fahrenheit.

....Do the tolerances get too close and the potential for a jammed
projectile increase significantly?

Where do the temperature differences start to matter presuming a slug or
solid projectile is used?

--
http://tinyurl.com/My-Official-Response

Regards,
Joe Agro, Jr.
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V8013-R

On Thu, 03 Jan 2013 14:58:00 -0500, Joe AutoDrill
wrote:

Guns and their projectiles are closely matched items.

What if the bullet is in the pocket of the shooter and is thus warm and
the gun is outside and at a fairly cold temperature of zero Fahrenheit.

...Do the tolerances get too close and the potential for a jammed
projectile increase significantly?

Where do the temperature differences start to matter presuming a slug or
solid projectile is used?

The projectile is forced into the barrel under high pressure..where
the Rifling digs deeply into the bullet and forces it to swell up and
fit snugly into the barrel grooves. Too big a bullet..and the bullet
gets longer and thats a bad thing.

Too small a bullet and the bullet wont be fully ingraved by the
rifling and it wont fill out the bore.,,also a bad thing.

About .000-.001 bigger than the bore size is normal and
usually..usually..supplies the best accuracy potential, all other
factors left out. Not all barrels are the same, some manufacturing
variation is expected up to .002-003" Wartime guns may be of a wider
spacing than that. The 303 Lee Enfield shoots a .311 bullet, but
barrels up to .315 are not uncommon in weapons that have been in
service for half a century.


When you push a fairly soft bit of metal down a barrel with between
30,000 psi and 60,000 psi...few things tend to hang up on its way out.

Numerous accounts of people shooting overly large projectiles from the
wrong sized barrel show that the bullet is USUALLY soft enough to be
squeezed down the barrel with no serious issues.

A case being an 8mm Mauser bullet being fired out of a 3006.

3006 bore diameter being .308 and the 8mm bullet being .323

In fact..I knew a guy who regularly shot 8mm surplus ammo in an old
Springfield O3 A4 in 3006 The cases came out with a gaping hole at the
end of the case where it swoll up hugely (the 8mm Mauser case is MUCH
shorter than the 3006) yet the bullets pretty much always came out of
the barrel of the gun each and every time.

In fact..he had purchased 1000 rds of 8mm mauser in the early
1950s...along with the rifle..and when I met him..he had about 200 or
so rounds left. The rifle was still safe to shoot.

Ugly as hell and the chamber had pitted badly..but..it still took pigs
that wandered into his back 40 at up to about 100 yrds

Temperature differences makes a small difference in bullet size..but
its not as critical as one would think. Keep in mind that firing a
rifle will cause the barrel to heat up very hot..and continue to stay
hot with each round. Machine guns will get so hot that the barrel
will get soft..and droop. Thats...hot. And a hot barrel tends to get
bigger, right along with the bullet.

Temperature of the Powder is been said to make more difference, from
cold shot to hot shot.

Nitroglycerine based gunpowders (virtually all fo them) will exhibit
some shot to shot differences when the chamber (and the round in the
chamber prior to firing) gets very hot.

Sometimes this will be in 100 fps+/- incements, others will be larger,
others smaller. This is largly due to the powder, how its laying
inside the case (they are seldom full to the bullet and some are more
air space than powder) etc etc

Gunner

The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie

On 2013-01-03, Joe AutoDrill wrote:
Guns and their projectiles are closely matched items.

What if the bullet is in the pocket of the shooter and is thus warm and
the gun is outside and at a fairly cold temperature of zero Fahrenheit.

...Do the tolerances get too close and the potential for a jammed
projectile increase significantly?

Where do the temperature differences start to matter presuming a slug or
solid projectile is used?


Sounds like a great time for an experiment, let us know.

My own answer is that the differences are minute and will not matter.

i

On Thu, 03 Jan 2013 17:18:03 -0600, Ignoramus9117
wrote:

On 2013-01-03, Joe AutoDrill wrote:
Guns and their projectiles are closely matched items.

What if the bullet is in the pocket of the shooter and is thus warm and
the gun is outside and at a fairly cold temperature of zero Fahrenheit.

...Do the tolerances get too close and the potential for a jammed
projectile increase significantly?

Where do the temperature differences start to matter presuming a slug or
solid projectile is used?


Sounds like a great time for an experiment, let us know.

My own answer is that the differences are minute and will not matter.

i


Oh they do indeed matter..and the closer to a Hot load on a cool day
you get..the closer you get to popped primers on a Hot day.

Some cartridges will exhibit this phenomina radicly with some
powders/bullet/primer configurations.

I once loaded a warmish load during mid winter that shot very well out
of a heavy barreled 22-250. Sub fractional inch groups.

Forward to July. Got set up on a nice ridge over a ground squirrel
colony and fired off my first shot. Pulled the case..and the primer
fell out. Fired the second shot...pulled the case..primer fell out.

Put the cases back in the box and took the rounds home, pulled the
bullets, dumped the powder back into the can and reloaded them with a
different well proven load. The summer heat caused that load
combination to reach at least 70,000 psi..not a good thing at all.

Gunner

The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie

"Ignoramus9117" wrote in message
...
On 2013-01-03, Joe AutoDrill wrote:
Guns and their projectiles are closely matched items.

What if the bullet is in the pocket of the shooter and is thus warm
and
the gun is outside and at a fairly cold temperature of zero
Fahrenheit.

...Do the tolerances get too close and the potential for a jammed
projectile increase significantly?

Where do the temperature differences start to matter presuming a
slug or
solid projectile is used?


Sounds like a great time for an experiment, let us know.

My own answer is that the differences are minute and will not
matter.

i

The temperatures won't be different for long.