Carnuba Blue - 9mm Polygonal Bore Walther

QUICK REWPORT: Lube & Reloading results

Just got back from range after shooting 50 rnds. lead through my Walther PPQ-M2 which has a poly' barrel. Water-Dropped WW cast 125 Lee RNFP's sized to .358 & pan-lubed with Carnuba-Blue over 3.6 of Titegroup.

Excellent results with them shooting as-well or better than Berry's 124 RNFP's and ZERO-ZERO leading in the bore.

Was very curious to see results as the majority of the internet seems to be so freaked-out about shooting cast lead in Polygonal Rifled psitol barrels.

Now will feel free to shoot many more at a session without concern. $0.00 Cost for 1,000 (or 10,000) 9mm reloading slugs (instead of $.08 each) sounds goods to me:grin:.

Way back in the day when the .40 Sqeak & Whistle was still new, a college buddy gave me the only personal firsthand account of being there when a Glock blew a case wall. He was working in the Gunsite smithy down in Arizona. Story was a dude in a class was up to about 700 rounds of lead without cleaning when it happened.

I shortly afterward did some one on one correspondence with an engineering type known online then as MarkCo. He had pressure tested shot by shot and had a nice track of increasing pressures as lead built up in the bore. We both agreed that never going more than 100 rounds before cleaning was a good rule.

Commercial lead bullets I bought about then leaded just about the worst of anything I had ever tried. And cleaning was a booger. I wound up asking around about whether there was something about Melonite treatment that made lead STICK very aggressively to that steel. Never found anyone who knew. My own theory was and is that the very, very hard surface from that treatment has the reputation and measured/quantified low coefficient of friction with other hard metals but those properties do not translate down into softer matchups probably including with aluminum alloys.

I just don't know enough materials scientists.

I have learned a LOT about shooting lead since then and am now convinced that good fit and any decent lube are the keys. Shot plenty of lead in OEM Glock and H&K USP (first generation polygon bore) barrels with no problems using my own bullets or RCBS Rifle lube or my Dad's old moly grease and Do-All bandsaw lube (it might have had 1 or 2 or 3 other ingredients...???).

So IMO the no lead in polygon barrels thing is an internet myth, true only for crappy bullets and people who don't pay attention.

Just looked and after about 120 rounds with my last batch of crappy bullets and I forgot which lube (??Tac-1??), one land and one groove are clean, the rest have some medium and thin lead streaking, none full-length and none even full-width of the land or groove. This batch keyholes about 1 in 10 shots at only 15 yards...less than 20 loads left.

YMMV. As always.

sorry, double post. Browser locked up.

My experience is that if your bullet is big enough and sufficiently hard then it will perform fine in polygonal barrels.