Velocity vs. barrel length

[txsendero]

What velocity difference should I expect in a .243 Win w/95 gr in a 22' barrel vs. a 26' barrel?

 

[6BR]

I would say about a 150fps to 200fps difference.

 

[RobertOly]

A good rule of thumb is 35-50 ft/in of barrel.

 

[habu]

I FOUND 10-15 FPS PER INCH WAS MORE LIKE IT.

 

[alf]

My Krieger 6.5-284 was cut back from 31' to 26', shooting the same load, lost 100 fps total, or 20 fps per inch.
I can't imagine a 243 losing more than that.

Al

 

[SDHandgunner]

Not sure about a 22' to 26', but I have tested 95gr. Nosler Ballistic Tips in both a 22' Ruger KM77RFP MKII and a 15' T/C Encore Handgun. The load used H-4350 Powder. Velocity results were 3071 FPS for the 22' Ruger and 2717 FPS for the 15' T/C.

The difference in the two barrels was 7' and the velocity difference was 354 FPS. In this instance the difference would figure out to 50.57 FPS per inch of barrel.

Never chronographed this load in a barre longer than 22' so I can not help there.

Larry

 

[txsendero]

Larry thanks for the info. What was the charge of H4350 you used to get the 3071 fps in the 22', and what primer?

 

[SDHandgunner]

I believe it was 42.5grs. with a Winchester Large Rifle Primer in Remington .243 Brass. Accuracy was better than my Varmint Loads in that Ruger with most 3 shot groups at 100 yards coming in at 1/2'.

Larry