New load development - COL R&D

[Hammbone]

I just picked up a new Tanfoglio Witness Elite Match in 9mm over the weekend. Sad to say, I haven't even had a chance to put a round through it yet.

I had previously spent a LOT of time and effort developing loads for my Beretta M9. Looks like I get to start all over again for this baby. Some initial investigation suggests this Witness isn't going to be as forgiving on COL. I've read some rules-of-thumb on here about figuring out MAX COL by making a dummy round and figuring out where the bullet just starts to touch rifling, then backing off 0.010" or so. Well, those numbers are less for the Witness than the Beretta. I'm just looking for a good starting point from folks who may have experience with this pistol.

My reloading inventory comprises of:

Bullets:

Bayou 147gr coated lead

Bayou 135gr coated lead

Berry's 147gr plated

FMP 124gr TMJ

Powders:

N340

HS-6

Power Pistol

Tite Group

Honestly, I don't compete (officially). I just hang out at a club with an indoor range and punch holes in paper. From time to time we have friendly accuracy grudge matches. So ultimately, I'm on the pursuit of accuracy more than quick follow-up shots.

[Hi-Power Jack]

So, your old ammo will not feed thru the new Elite because it's too long?

If it's just a matter of OAL, I'd use the exact same load, but seat the bullets

a little further in, for the Elite.

Then, I'd try those new shorter rounds in your M9.

See if that's accurate enough for you ... and Velocity is okay.

You might be able to get away with just one load that works well

in both guns with just a simple change of OAL.

[LilBunniFuFu]

I agree with Jack as long as you aren't near max for powder. Since this is 9mm most likely at minor PF levels then there should be no problem, if this was major ammo I would say to back off on powder and oal then work up again.

[Hammbone]

Thanks for the replies guys.

So, your old ammo will not feed thru the new Elite because it's too long?

If it's just a matter of OAL, I'd use the exact same load, but seat the bullets

a little further in, for the Elite.

Yes, I do have an issue with my 135gr Bayou bullet loads. These are loaded to 1.155" COL. My dummy "max-length" round I have tells me the bullet starts to engage rifling at 1.130". With the gun disassembled and barrel in my hand and I drop this round in the chamber, it's obvious that the bullet prevents the case from seating on the front edge. So I do have an issue there.

I agree with Jack as long as you aren't near max for powder. Since this is 9mm most likely at minor PF levels then there should be no problem, if this was major ammo I would say to back off on powder and oal then work up again.

Unfortunately, nobody lists data for 135gr bullets for 9mm. What I do is, for a starting point, I linearly interpolate start and max loads based on data from 124gr and 147gr. I start at the lowest and work may way up slowly while chrono-ing every load. Based on linear interpolation, I'm at what I think is near max load. I'm using 3.8gr of TiteGroup. Velocity is 1060fps, so PF is 143. I'm a little nervous about just seating the bullets deeper another 0.020"-0.030".

I actually sold my M9, so two things: 1) I can't use these rounds in it any more, 2) but I can focus on optimizing loads for the Witness. I've only got 50rds made up this way, so it's no big deal if I have to pull them all. (I sold the M9 because I don't see myself ever using it again - and I'd like to focus on optimizing one set-up versus being only okay at multiple).

Ultimately, I'm really inquiring to see what folks have to say about what COL's work best for them in their Witness Elite Match's. I understand I may find a COL that is best for accuracy but may not feed well. With no knowledge going in, I have a lot of ground to cover to figure out what she likes. I just thought I'd get some input if others have already been down this path with this particular gun.

Thanks.

[Justsomeguy]

Truly, OAL is GUN and BULLET specific. There is no way, unless someone has used the exact same bullet as you, to forecast an approximation of the OAL you will be using. I have several Witness pistols though, and I can tell you that even with some lead round nose types, I have had to use OALs as short as 1.045, and with some lead flat nose I was down to 1.015. So... be aware that you may be using OAL lengths that are kind of scary short compared to what some other gun types can handle. I am still contemplating buying a throating reamer just to get the OALs up into the range that I can use in several of my other guns so I won't have to load specifically for the Witness types at very short OALs.