Plated Bullet comparison.

[scooter123]

Just tried out my new Shooting Chony on some 40 caliber reloads featuring bullets from Berry's and Hunting Shack. Berry's has the spec for diameter at 0.401 and HSM has them at 0.400, so there is a minor difference in the diameters. I was curious to see if it would have any effect on velocity so loaded up both brands using 5.2 grains of IMR SR7625 with 180 grain bullets.

The results were sort of what I expected, both brands of bullets produced 960 fps from the 3.9 inch barrel in my Sig P229. BTW, this particular loading is basically a match for the 40 caliber Federal Champion from Walmart. Had a round of the Champion with a sideways primer so I broke it down and was surprised to see that the bullet is either an exceptionally seamless TMJ or a Plated Lead bullet. Apparently FMJ can mean a rather wide variety in the composition and method for producing the jacketing.

Final note on the SR7625. I can recommend this particular powder with 5 stars. It burns very cleanly and meters PERFECTLY in my Lee Perfect Powder Measure.

 

[rsrocket1]

If you slugged your barrel, you would see that it is just about at the 0.400" mark meaning that both bullets are sealing up the barrel properly. Even if the HSM's were a little small, the pressure may have bumped the bullet enough to seal the bore.

Good to hear that you can load up a round to do what you want and you have the flexibility to use a variety of bullets.

 

[WR Moore]

Every TMJ bullet I've ever seen has been a plated bullet.

 

[Calliope]

I have some Hornady TMJ's that are jacketed with a copper disc at the base, but most TMJ's are plated I think.

SR 7625 is a great powder. I use it a lot in 9mm and .38 Super. SR 4765 is another great powder that is under appreciated.

 

[blujax01]

Scooter, sorry to take this thread adrift but:

Scooter spoke of FMJ Full Metal Jacket Champion bullets as opposed to the plated bullets from Berry's and Hunting Shack. Response #'s 3 and 4 spoke of TMJ (Total Metal Jacket?) as if they are the same as FMJ?

I have been under the impression the FMJ is jacketed, not plated, and can be loaded up to full potential.

I do not know a lot about TMJ.

Is there a difference?

If so, what?

Thanks and apologies again to Scooter123.

 

[Arub]

TMJ = Truncated (flat nose) Metal Jacket. Is a metal jacket, not plated.

 

[Calliope]

TMJ = Total metal jacket.
Can be plated or jacketed with a disc at the base, depending on the manufacturer.
Speer TMJs are plated, Hornady TMJs are jacketed with a disc.