Not getting velocities as posted in Hornady RL manual on 6.5PRC

[Dan swainston]

I am loading RL 23 with Hornady 140 grain eld-m and Berger 140 grain vld Bullets Norma brass and federal match lr primers. Following the Hornady reloading manual.
shooting .19" groups but velocities are not even close.
24" barrel
here are the results from the labradar

		RL 23 grains	FPS avg	Delta FPS
		53.5	2809
		54.1	2,854.2	45.2
		55	2908	53.8

Just not understanding what the book states at 54.1 grains it should be pushing 3050 FPS but at 2854.2 is a 6% reductio. Any thoughts would be helpful. The guns shoots just wanted more velocity that is why I justified it over the 6.5 creed moore. I have three of them.
How far can I push over the recommended levels checking primers and pressure signs. I have shot about 80 rounds through the gun with standard break in. picture is 10' target at 1,000 yards slight breeze pushing left.

 

[GLTaylor]

Some barrels are just slow. You may have one. Your speed-up process should be about there. Have you kept up with velocity increases. During break- in?

 

[DoneNOut]

Hornady data based on 26" barrel at 70F. You got 24" and most likely shooting in colder denser air. It all makes sense.

 

[Lab rat]

Feed it some RL26 and you will find some speed

 

[rammac]

You are using a different bullet, a different case, and a different barrel length, no wonder you're getting different velocities.

 

[rharfo]

It took 200 rounds to get 100 FPS gain out of my HS precision rifle. So like you I had a fast creedmore until it grew up and started acting like a PRC!

 

[Dan swainston]

Feed it some RL26 and you will find some speed

Just haven't been able to find any

 

[Dan swainston]

You are using a different bullet, a different case, and a different barrel length, no wonder you're getting different velocities.

Same Norma cases 90 % hornady
Thanks for your solid recommendations

 

[jpope02]

You might have to choose between accuracy over speed especially if you use Hornady brass. I have 2 PRC's and have used nearly all Hornady's of reloading data and have never gotten their advertised speeds in any of my PRC's without pressure problems. RL26 & H1000 seem to be more consistant than their other listed loads but I still get pressure when near >2950 fps.

 

[Muddyboots]

What is the COAL for the load? Max COAL is 2.955 which may be also part of the equation. A shorter COAL sometimes generates more velocities with case density, pressure, more bullet in case et al. I've seen it with several other bullets (i.e.190ABLR) in 300WSM.

Brian Litz:
Effects of Seating Depth / COAL on Pressure and Velocity
The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space. Another way to look at this is you have to use more powder to achieve the same pressure and velocity when the bullet is seated out long.

 

[PowellSixO]

It's two things. One, new brass uses energy to form to the chamber on its first firing. Two, it takes 150-200 rounds for a barrel to break in. Once it's broke in, you should gain significant FPS.

 

[243winxb]

Powder burn rate from lot to lot can be as much as +/- 5% difference with some powders.

 

[jasonco]

There's a whole lot of different circumstances, going on with your loading and when the Hornady data was produced?!

 

[Trm82]

Norma brass

I did'nt think Norma had Brass for the 6.5 PRC yet !!!!