6.5 PRC - slow barrel?

[matchbook454]

I have a new Weatherby Vanguard in 6.5 PRC. The barrel is 24”. I’m loading Lapua brass with Reloder 26, Fed. 210’s, and Hornady 147 ELDMS. Hornady shows 55.7 gr. Max. With a muzzle velocity of 3050 fps. I’m loading 56.8 gr of RL-26 and am only getting 2820 on my Magnetospeed. I’ve worked up to 60.0 gr without seeing pressure signs other than a little bit of a sticky bolt. Magnetospeed reeds fine on 2 other rifles so I don’t think there is error there. I’m also shocked that I have loaded up to 60 grains - 4.3 grains over Max without ejector marks, flattened primers, etc.. Could this be just a slow barrel? Any thoughts, suggestions, etc. are appreciated. FYI, rifle has just over 100 rds. fired.

 

[pikespeakgoat]

Definitely slower than my barrel......I'm loading 54.5 RL 26, CCI 200, 147 ELDM and Hornady brass in my Ruger American which has a 24" barrel, 1/8 twist.

At 2.955" which is .030" jump, 2.310" cartridge base to ogive, I'm running 2890 fps via Magnetospeed V3. My dope holds up to 1k + with those numbers. I just loaded to duplicate factory vel and length since they shot so well.

 

[MT257]

Hornady data is also done with a 26” tube. Yours is a 24. I’ll compare my results with yours in the next few weeks as I begin working loads up in a vanguard prc.

 

[matchbook454]

Hornady data is also done with a 26” tube. Yours is a 24. I’ll compare my results with yours in the next few weeks as I begin working loads up in a vanguard prc.

I still expected to be closer, I’m a few hundred FPS slower than I should be. Let me know what you get with yours. Good luck!

 

[Straightshooter1]

I still expected to be closer, I’m a few hundred FPS slower than I should be. Let me know what you get with yours. Good luck!

Using pikespeakgoat's data in my QuickLoad app, here's some numbers that might help give you some ideas:

View attachment 1390823

 

[matchbook454]

Using pikespeakgoat's data in my QuickLoad app, here's some numbers that might help give you some ideas:

View attachment 1390823

At 56.8 grains I should be way over pressure which I do t see pressure signs. And I’m also at 2820 fps, not 3000. Weird!

 

[matchbook454]

Something happened to your last message but I thought it showed 2819 fps for like 54.5 grains?

 

[Straightshooter1]

At 56.8 grains I should be way over pressure which I do t see pressure signs. And I’m also at 2820 fps, not 3000. Weird!

Pmax is at 64991 psi, so it's not really "way over" pressure, but just at the max for that data. If I use the default burn rate that QuickLoad uses, then you're load looks like this (still higher than what you're getting):


Other factors can be at play, like temperature, COAL's/seating-depths, case volumes or a combination of things where that can be that much difference. . .???

 

[matchbook454]

That is looking closer. And I am shooting at lower temps - 50-55 degrees. I measure BTO but will check COAL and compare. Thanks so much for sharing this. I’m feeling a little better about my rifle now! I will say that it is pretty accurate for a factory rifle. .350” groups at 100 yards. I’ve shot out to 400 with it as well and it’s been good. I will do a lot more shooting at longer range out to 1,000 yards after the end of the year.

Thanks again for your help!
Joe

 

[MT257]

So I went and did some seating depth tests today with 140 partitions and rl-26. Loaded at 54gr and all of my velocities were around 2845-2855 fps. Nosler shows that I should be near 2960ish. I had to seat these shorter than 2.955 because of where the ogive is on the partition in relation to the longer bullets such as the eldx. So yes my Weatherby vanguard is also slower than the published data.

 

[matchbook454]

So I went and did some seating depth tests today with 140 partitions and rl-26. Loaded at 54gr and all of my velocities were around 2845-2855 fps. Nosler shows that I should be near 2960ish. I had to seat these shorter than 2.955 because of where the ogive is on the partition in relation to the longer bullets such as the eldx. So yes my Weatherby vanguard is also slower than the published data.

Thanks for sharing your findings! I’m glad that it’s not just me doing something wrong. I’m a little disappointed that I’m not getting the speed that I hoped for but am hoping this thing speeds up after another 100 or so rounds. I will say that I am happy so far with the accuracy. I feel confident shooting out to 600 yards with it. I’ll probably get out shooting again right after Christmas and will let you know how things go.

 

[JB10]

I have shot the 147 with r26 before but did not checked my speeds. Im currently using 156 at 2,916fps from a 24 inch barrel with N565