Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Need advice on testing during load development
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="Jesse09" data-source="post: 1108218" data-attributes="member: 88547"><p>I'm developing a hunting load for a new 270WSM. Muzzle velocity is from low 3400's to low 3600's, with a projected barrel life anywhere from 500-1000 rounds. Because it's a barrel burner, I don't want to spend any more shots, generating any more heat, than I have to while developing the load.</p><p>Here in Georgia the ambient temperature (I'm on the bench at daybreak) will rise from the low 70's F to the upper 80's F during the time I'm shooting. </p><p>My usual procedure is to load five 3-shot groups, varying only one component (seating depth or powder charge) among the groups. I'll cool the barrel between shots (not groups) by placing the rifle in a modified cooler. I shoot "round robin" groups, meaning I shoot only one shot at each target before moving to the next, finally completing all five groups in about three hours.</p><p>So, the barrel is cooled to pretty much the same temperature for each shot; however, the ambient temperature is steadily climbing, so that there may be as much as a 12*F rise between a group's first and third shot.</p><p>I could eliminate the effects of the rising ambient temperature by firing all three shots at a given single group in the space of a few minutes, then cooling the rifle before moving on to the next group. That would mean, though, that the barrel temperature would rise a lot higher than I'm comfortable with, given the 270WSM's high MV. I'm concerned that: (1.) I'd be shortening barrel life at those temperatures, and (2.) the rapid heat build-up between shots 1 and 3 would distort the point of impact on the target.</p><p>Remember, I'm developing for hunting, not benchrest; so, I want a load that consistently delivers its best one shot at a time from a cold (or ambient temperature) barrel.</p><p>Thanks for your recommendations.</p></blockquote><p></p>
[QUOTE="Jesse09, post: 1108218, member: 88547"] [B][B][/B][/B]I’m developing a hunting load for a new 270WSM. Muzzle velocity is from low 3400’s to low 3600’s, with a projected barrel life anywhere from 500-1000 rounds. Because it’s a barrel burner, I don’t want to spend any more shots, generating any more heat, than I have to while developing the load. Here in Georgia the ambient temperature (I’m on the bench at daybreak) will rise from the low 70’s F to the upper 80’s F during the time I’m shooting. My usual procedure is to load five 3-shot groups, varying only one component (seating depth or powder charge) among the groups. I’ll cool the barrel between shots (not groups) by placing the rifle in a modified cooler. I shoot “round robin” groups, meaning I shoot only one shot at each target before moving to the next, finally completing all five groups in about three hours. So, the barrel is cooled to pretty much the same temperature for each shot; however, the ambient temperature is steadily climbing, so that there may be as much as a 12*F rise between a group’s first and third shot. I could eliminate the effects of the rising ambient temperature by firing all three shots at a given single group in the space of a few minutes, then cooling the rifle before moving on to the next group. That would mean, though, that the barrel temperature would rise a lot higher than I’m comfortable with, given the 270WSM’s high MV. I’m concerned that: (1.) I’d be shortening barrel life at those temperatures, and (2.) the rapid heat build-up between shots 1 and 3 would distort the point of impact on the target. Remember, I’m developing for hunting, not benchrest; so, I want a load that consistently delivers its best one shot at a time from a cold (or ambient temperature) barrel. Thanks for your recommendations. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Need advice on testing during load development
Top