PNW Guns Forum
Go Back   PNW Guns > PNW Guns > Reloading

LinkBack Thread Tools Display Modes
Old 05-23-2013, 07:17 AM   #1
Joined: Nov 2009
From: Graham, Wa
Posts: 240
Comparison of barrel twist to bullet weight

Just an interesting look at how different bullet weights perform out of the same barrel. This is obviously not an exhaustive list, I was just playing around with some loads. 3 bullets: Hornady 55gr VMAX, Hornady 60gr VMAX, and the Nosler 77gr Custom Competition HPBT. All are loaded in once fired NATO brass, loaded to 2.26 OAL with Remington 7 1/2 primers and Hodgdons H335. I haven't tested the powder charge or tried to perfect the jump to rifling. I just chose a "middle of the road" charge and shot. I also have a box of Berger 70gr VLDs that I wanted to include, but I haven't quite figured out the details on that load, so I didn't shoot them.

Rifles used were a 16in, 1/7 stainless FN barrel (ST), and a 20in, 1/8 heavy match barrel (RG). It was drizzling a bit, and right at 55 degrees. 100yds.

ST, 55gr VMAX, 25.5gr H335. 1 3/4 inch.

ST, 60gr VMAX, 25gr H335, 1 3/4 inch.

ST, 77gr N-CC-HPBT, 23.5gr H335. Less than 1/2 inch (!!)

RG, 55gr VMAX, 25.5gr H335. Just a hair under 1 inch. Ignore the holes to the far right, just the holes bracketed by the marker.

RG, 60gr VMAX, 25gr H335. Over 2 inches.

I shot the 77gr N-CC-HPBT out of the 20 inch 1/8 barrel, but my groups were too big to get a decent picture. My groups were in the neighborhood of 6-8 inches. You can see that the rifle really liked the 55gr bullet, and then really started opening up on the 60gr. This confused me as a tighter twist like the 1/8 should love heavier bullets, and over stabilize something as light as 55gr. But clearly, it really likes the 55gr. I will take out some 50gr VMAX next time and see what happens.
Join PNW Guns

Welcome to PNW Guns, a gun and firearm community for gun owners in the Pacific Northwest. We welcome everyone and the community is free to join so register today and become part of the PNW Guns family!

Old 05-23-2013, 07:28 AM   #2
Joined: Nov 2009
From: Graham, Wa
Posts: 240
What really struck me was how "finicky" the longer, match barrel was. 1/8 should be more "tolerant" of a wider range of weights than the 1/7, and as a match barrel, should be more accurate. But clearly, the 16 inch barrel with a 1/7 twist was able to at least hold a decent "minute of combat" group with a wider range of bullets. And damn, 1/2 in group with a 16 inch barrel? I'll take that any day..

  PNW Guns > PNW Guns > Reloading

barrel, bullet, comparison, twist, weight

Thread Tools
Display Modes

Facebook @pnwguns PNW Guns RSS Feed

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.6.0 ©2011, Crawlability, Inc.
Copyright 2009 - 2010 PNW Guns. All rights reserved.