Is this significant?

[Think293]

I've got a 9mm load that shoots exceptionally clean and accurately in my Glock 17. It's 4.0 grains of titegroup under a 124 grain LRN bullet at 1.125" OAL. It runs at ~1050 ft/sec with no signs of over pressure. That is just slightly below the published velocity that corresponds to a chamber pressure of ~30,000 psi.

Everything good so far.

The same load is too long in my Walther PPS. I made some dummy rounds at 1.110" and they feed well. I know that shortening the OAL will increase the pressure, but is 15 thousands significant or should it be safe?

I haven't been reloading long enough to have a sense of what is significant and what isn't. What do you guys think?

 

[KansasSasquatch]

I would definitely reduce the charge to 3.6gr and work up. Fast burning powders like Titegroup can be pretty sensitive to small changes like that.

 

[LiveLife]

Welcome to THR.

+1. I would load 5-10 rounds of 3.6, 3.7, 3.8 and 3.9 gr and see which charge produces the best accuracy and go with that load.

Hodgdon load data

125 gr Lead Cone Nose Titegroup OAL 1.125" Start 3.6 gr (1002 fps) 22,900 CUP - Max 4.0 gr (1096 fps) 30,400 CUP

 

[gamestalker]

The key guideline for pressure compensation I personally use is .010" or more. So yes, definitely reduce a bit and work back up, just for safety sake, after all, better safe than sorry, especially with a fast powder like TG.
GS

 

[Otto]

What do you guys think?

TG at it's max loadings can be very spikey and exceed maximum SAAMI pressures quickly. If a novice is determined to load to the MAX, he'd be wise to avoid TG.

 

[thump_rrr]

I will be the one that gives a dissenting opinion.
This load barely makes IPSC minimum power factor by 4%.
There is no way that those loads won't be safe to shoot with .015" more setback.
At the same time it's not my face and fingers on the line so proceed at your own risk.

 

[ArchAngelCD]

I'm so satisfied with W231 I don't bother with Titegroup or hardly any other powder either. I use 4.0gr W231 under a 124gr LRN bullet in the 9mm and it's a great load for me. (4.4gr W231 under a 124gr FMJ bullet)