I'm getting better at Identificatin

[Kilroy]

This is mostly for Hazord, who has helped me time and again on the confusion between the American 3 inch M2, the 75mm Sherman, and the 76mm improved Sherman, whose name I do not recall but is in a long straight case, usually steel.

I picked up a 1943 M2 3 inch round for an M10 tank Killer. I now have an example of all three. This was the longest in waiting to find.

The photo of the headstamp is very crusty, I am looking for some kind of cleaner that would remove the dirt this case got in the last 70
years, yet leave a nice even patina all over.

Any suggestions on a very mild cleaner that would leave the patina and yet remove just dirt? The headstamp is almost impossible to read,
and that is partly due to the dirt filling the incised letters. Two crossed cannon can faintly be seen there, but a gentle cleaning would probably do some good.

So here it is, one of my mystery shells...

Walt

 

[HAZORD]

That is a nice looking round. The M79 AP-T projectile is tough to find unfired.

Everyone here probably has their method of cleaning brass. There are chemicals that reloaders use to clean their firearms brass. Most acids will remove the grunge, but the stronger ones have side-effects. I used some Naval Jelly once, which is a fruit acid. It will remove rust too. the problem with brass, was that I think it removed some of the zinc from the surface, which then gave the brass case an unnatural red tint. So stay away from Naval Jelly and acids in general. One method might be some Brasso as is used to polish military belt buckles etc.

 

[Yodamaster]

Did you try the ink eraser ? You know, the blue side of a bicolor eraser ! I use it to clean old coins ! It is very sweet and effective.


Yoda

 

[highlandotter]

Soaking in WD 40 works pretty well for me. Then use fine, brass HAND brush.

 

[Slick]

Flitz and/or bronze wool.

 

[Kilroy]

Soaking in WD 40 works pretty well for me. Then use fine, brass HAND brush.

I have duly noted the suggestions of all you fellows, this thanks goes out to all of you, I will probably try the WD-40 idea since I have that handy and some steel wool too, but I may try it on a test surface first.

Thanks for the evaluation Hazord, I did not realize the projectile was particularly rare. I do know that I have only seen one other of these rounds for sale over the years, and it was a lacquered steel case in VG condition, but when you can get brass it seems like it is usually the preferred metal unless a steel case for that type is rare.

It seems a shame they didn't load up that case and send out that shot at 3000 fps instead of keeping it at low velocity to spare the barrel for a projected longer life. That case could probably easily hold 5lbs of propellant and get close to a Firefly in velocity. A tank killer was so poorly armored probably a German Pak36 could hurt it at range. They probably did not live to see many barrel changes if they had a mortality rate similar to the Sherman.

Walt

 

[HAZORD]

A few things to mention. Steel cases in good condition for this gun are much more rare than the brass ones. They usually have rusty headstamps because people stood them on the head on concrete and the chemicals in the concrete corrode the head. The AP-T projo M79 that you show was not the preferred projectile because it was just a solid shot. Of course the HVAP would have been the preferred, but the U.S. didn't have the Tungsten needed for the cores. The UK had Tungsten and therefore developed the APDS projo for the 17 Pdr on the firefly and it was the preferred gun for killing Panther tanks. The next preferred projo for the 3 inch gun would have been the APCBC-T with HE fill for penetrating and then exploding. It was the same projo used in the Sherman, but with a different rotating band for higher velocity and of course more case capacity. As far as velocity goes, Breech and Chamber metallurgy in WWII wasn't at all advanced in U.S. guns. If you look at a current 120mm projectile, they are moving at around 6,000 fps, more than twice the velocity of these 3 inch projos. 105mm APDSDS-T ammunition issued to the tanks used in the first Gulf War actually specified which breech ring serial numbered guns they could be fired in, as the newer guns could take the pressure whereas the older guns would have blown apart, so the metallurgy is still advancing to build guns that can take more pressure. Yes the 3 inch gun had room in the case for more powder, but the chamber couldn't handle the pressure.

 

[Kilroy]

Yes, when I made that comment about just pouring on the propellant i was in my own mind cognizant of there being many other considerations to the throwing of a projectile faster than several more pounds of powder. Hell, as a re loader of 20+ years I have learned ( sometimes the hard way ) what even a little over the limit can mean if you make a mistake in the wrong direction, or just pain don't know what you are doing.

It is possible to have as disasterous a result from way underloading a round than overloading if the powder involved will not tolerate that type of exceeding of it's limits.

There is a lot of engineering involved, then testing, evaluation of results.....all this is essential in the planning behind increasing the muzzle velocity of a given projectile. It is not nearly as easy as just increasing propellant.

Might there be a sectioned example of an HVAP in the archives here? I think I will look.

Thanks,
Walt

A few things to mention. Steel cases in good condition for this gun are much more rare than the brass ones. They usually have rusty headstamps because people stood them on the head on concrete and the chemicals in the concrete corrode the head. The AP-T projo M79 that you show was not the preferred projectile because it was just a solid shot. Of course the HVAP would have been the preferred, but the U.S. didn't have the Tungsten needed for the cores. The UK had Tungsten and therefore developed the APDS projo for the 17 Pdr on the firefly and it was the preferred gun for killing Panther tanks. The next preferred projo for the 3 inch gun would have been the APCBC-T with HE fill for penetrating and then exploding. It was the same projo used in the Sherman, but with a different rotating band for higher velocity and of course more case capacity. As far as velocity goes, Breech and Chamber metallurgy in WWII wasn't at all advanced in U.S. guns. If you look at a current 120mm projectile, they are moving at around 6,000 fps, more than twice the velocity of these 3 inch projos. 105mm APDSDS-T ammunition issued to the tanks used in the first Gulf War actually specified which breech ring serial numbered guns they could be fired in, as the newer guns could take the pressure whereas the older guns would have blown apart, so the metallurgy is still advancing to build guns that can take more pressure. Yes the 3 inch gun had room in the case for more powder, but the chamber couldn't handle the pressure.