has anyone tried to duplicate underwood ammo?

[wadcutter]

I've been reading a lot of the pulldown results of Underwood's 10mm ammo and the components are nothing the average reloader can't find. Has anyone tried to duplicate these loads? If so did you chrono them and what were your results?

[The_Shadow]

I have duplicate a few of the 10mm with IMR800x and LongShot and 9mm rounds with AutoComp, Some of these others I haven't played with as much, but the 44 and 357 using H-110 or 296 are fairly straight forward book loads at Hodgdon and even LilGun loads are very close to book loads with some being over. 

While the "Pull-Downs" are meant as a reference of what was found, I would still work up from the book data and if you are using different components (bullet, primers, brass, etc.)things will probably need to also change.

[Geeman]

With much appreciation of Shadow's, Intercooler's, Raggedyman's work and Grim Reapers providing a home for it all, I use these results as an additional resource to load the 10mm. 

I especially like the old 800x loadings for the discontinued factory loadings as they seem to make for the most potent, safe loadings I've put through my guns.  Start lower!!!!   Work up to those loads.  800x is for weighed charges only, but it does seem to get the most out of the 10mm.

Greg

[Raggedyman]

I agree with the 800X. I actually stop a little short of Underwood for my town and woods defense loads. I think Underwood pushes the projectiles way beyond their design limits.

[denclaste]

I have to agree with Raggedyman. There seems to be a point of very rapidly diminishing returns that is reached with some of Underwoods loadings. Unless the projectile is specifically designed for those velocities you can run into integrity problems that aren't seen at 100 fps slower velocities. If the bullet wasn't designed to use at those speeds, what have you gained?

[Intercooler]

  Utter and total devastation 

[nickE10mm]

I've been reading a lot of the pulldown results of Underwood's 10mm ammo and the components are nothing the average reloader can't find. Has anyone tried to duplicate these loads? If so did you chrono them and what were your results?

Yes.    (Many of us have been there, done that, years ago.) 

Most of us have found loads we are most comfortable for our intended use and observed performance and accuracy that may, or may not, equal the velocity Underwood ammo attains.