Short barrel 6.5 prc

Great data! 20" seems to be a sweet spot
Not sure that's conclusive. It's a single charge weight and loss for fps for h1000. Those speeds are really low for 140. IMHO the conclusion is that 25 fps loss per inch applies from 18-26" in a single controlled test. 16-18 is a bigger jump likely due to the powder burn rate. My 22 vs 18 shows 25 as the difference per inch for 560 and rl 26 as well.
 
Correct. The chart is meant to show a baseline for velocity changes. It is not a maximum velocity test at each barrel length. However, with this data and a base line factory 147 speed, extrapolations may be made for higher net velocities.

I have seen online reports of short barreled PRCs and SAUMs with MVs with reloads ranging over 200 fps per given barrel length. YMMV
 
Correct. The chart is meant to show a baseline for velocity changes. It is not a maximum velocity test at each barrel length. However, with this data and a base line factory 147 speed, extrapolations may be made for higher net velocities.

I have seen online reports of short barreled PRCs and SAUMs with MVs with reloads ranging over 200 fps per given barrel length. YMMV
I can see that. I know I have zero issue running a 140 at 2950 vs the 2765 shown for an 18. I think the exercise was simply to pick a charge and do a length test, makes sense. I just don't know that 20 is more or less optimal then other other lengths. I suppose if you have a target fps in mind and know it's roughly 25-30 fps loss then you work back from that. Now that I think it through, that seems to be what you are saying, ie the factory 147 fps example a 26 to 20" shows 3010 - 150 = 2860.
 
You are correct. Looking to post more of the testing that was done. Some of the other data was with 129 grain bullets and suppressed vs. unsuppressed. Just as a teaser.

Before doing the test, I did some research for published data on MV changes in barrel lengths. I couldn't find anything in the PRC case type. On the charts I did find, for larger bore rifles (.223 aside), 20" does seem to be the starting edge of the muzzle velocity "cliff". That doesn't mean you will loose all of it below 20", just more per inch. I wanted to find out how much more per inch with the PRC case.
 
Maybe this is helpful. The average is 30.2 with the 16-26: 18-26 is 24.5: 20-26 is 23.1

Barrel lengthAverageFPS DiffLoss per Inch
26​
2961​
0​
0​
24​
2921​
-40​
-20​
22​
2888​
-33​
-16.5​
20​
2822​
-66​
-33​
18​
2765​
-57​
-28.5​
16​
2659​
-106​
-53​
 
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Maybe this is helpful. The average is 30.2 with the 16-26: 18-26 is 24.5: 20-26 is 23.1

Barrel lengthAverageFPS DiffLoss per Inch
26​
2961​
0​
0​
24​
2921​
-40​
-20​
22​
2888​
-33​
-16.5​
20​
2822​
-66​
-33​
18​
2765​
-57​
-28.5​
16​
2659​
-106​
-53​
For me, I could handle losing 75fps to go from 26" to 22". But not losing 300fps from 26" to 16".
 
Gotta ask why the f*#k anyone would want to corrupt a fine long range cartridge by chopping the barrel. My PRC is choice for >700 yard competition
Handy as can be for hunting out west is the only reason I did! After packing a 28 inch barrel around for years, I decided I was sick of the getting snagged on every bush and tree limb. For competition use though 26 is the way!
 
For me, I could handle losing 75fps to go from 26" to 22". But not losing 300fps from 26" to 16".
Can't blame you. However, the point for most of this is more about desiring a short barrel rifle for use with a can, lightweight, or for handling/carrying etc. So while going down this road and desiring x fps out of y bullet you have choices to make. For example people will say well just get a creedmoor vs a PRC. No, it's not apples to apples. A sherman, saum, or PRC in a 6.5 will far exceed a creed inch for inch. So, it boils down to whether a 140 grain bullet at 2800 fps is going to work for you. If so, then you can decide what barrel length and cartridge gets you there within your parameters. I only went the route of a 18 due to the way in which I carry the rifle coupled with can. I actually like the 22" better for the performance but the 18 is no slouch and does much better than I expected.
 
Gotta ask why the f*#k anyone would want to corrupt a fine long range cartridge by chopping the barrel. My PRC is choice for >700 yard competition
It's a hunting page, not a comp page. Weight, handling, carrying, etc...... It all becomes a sum game of what works for you. There is no right or wrong unless terminal ballistics is not adequate for the range you are hunting.
 
Can't blame you. However, the point for most of this is more about desiring a short barrel rifle for use with a can, lightweight, or for handling/carrying etc. So while going down this road and desiring x fps out of y bullet you have choices to make. For example people will say well just get a creedmoor vs a PRC. No, it's not apples to apples. A sherman, saum, or PRC in a 6.5 will far exceed a creed inch for inch. So, it boils down to whether a 140 grain bullet at 2800 fps is going to work for you. If so, then you can decide what barrel length and cartridge gets you there within your parameters. I only went the route of a 18 due to the way in which I carry the rifle coupled with can. I actually like the 22" better for the performance but the 18 is no slouch and does much better than I expected.
20" 6.5SS suppressed. Mean medicine for a light pack rifle. 130 OTM @ 3075, 140 Hyb @ 3033, or 156 Elite @ 2916fps. Pick your poison.
 
20" 6.5SS suppressed. Mean medicine for a light pack rifle. 130 OTM @ 3075, 140 Hyb @ 3033, or 156 Elite @ 2916fps. Pick your poison.

Think we are missing each other. The numbers posted for that PRC are ridiculously low so if you are thinking that is what a PRC does, well, it's way off. Way off. He was just using the barrel length and charge as indicator of loss. Definitely not even remotely close to a tuned load.
 
Gotta ask why the f*#k anyone would want to corrupt a fine long range cartridge by chopping the barrel. My PRC is choice for >700 yard competition
Because with a suppressor screwed on a normal length barrel is way to long. Really anything over 25" of total barrel length is to long when I have a gun in my Kifaru gunbearer for hiking in the dark. Barrel blocks my headlamp and it's just annoying
 
Think we are missing each other. The numbers posted for that PRC are ridiculously low so if you are thinking that is what a PRC does, well, it's way off. Way off. He was just using the barrel length and charge as indicator of loss. Definitely not even remotely close to a tuned load.
I agree, his numbers are way too low. The PRC numbers should be closer to my numbers. Maybe not quite there, but close. And those numbers work really well on deer-sized game in a light, short, handy pack rifle.

I have shot a "few" 6.5PRCs, and they are normally much faster than those numbers provided. And I don't even run RL26 in them.
 
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