MY Dumb Question Of The Day - Polygonal Rifling

I’ve read that H & K pioneered its development and use, and that it’s supposed to put more “squeeze” on the bullet, to improve accuracy - does anyone know what other pistolmakers have gone to it? How about its use in rifles? Too expensive to produce? Not practical? If it HAS been adopted by others, it’s not showing up in the ads I’ve seen. If its use is that significant, it could be an answer to accuracy problems in smaller compact and sub-compact guns.

1 Like

Kahr pistols – at least the more expensive K series – use polygonal rifling. I believe that some Walther firearms do, as well.

My Glock 43xMOS has it.

I don’t like quoting Wikipedia, but you can always check their references at the bottom:

Wikipedia: Polygonal rifling

If I remember correctly, for a full size, 9mm barrel, the increase in velocity was about 15 fps (around 1.3%). However, I think that figure is significantly less than actual velocity loss/gain due to typical ammo QC from one bullet to the next.

For the Kahr, the p and K series are supposed to have it, and the C series doesn’t (unless they changed in the last few years. I don’t really notice a difference, but I haven’t done a side by side test.

Quote from Wikipedia:

…precision target pistols such as those used in Bullseye and IHMSA almost universally use traditional rifling, as do target rifles. The debate among target shooters is almost always one of cut vs. button rifled barrels, as traditional rifling is dominant. Polygonal rifled barrels are used competitively in pistol action shooting, such as IDPA and IPSC competitions.

1 Like