6.5 CM impressive group, but low FPS???

My 20" Tikka CTR pushes the 130gr Sierra TGK over 42.0grs RL17 @ 2750 fps. Quickload suggests if I chopped the barrel to 16.5", velocity would be 2611 fps

Same bullet, 41.1grs RL16 does 2650 fps from 20", predicted speed from 16.5" is 2509 fps
 
VV site says they used a 25.5" bbl on it, 130gr @ 2420 to 2440 at the start load, so, with a 16" ,you are pretty much bang on to where you should be with your velocity. You know what you have there now, try running it up a bit and see whether it works or not. Nothing to lose by trying and would help you downrange a good bit, in finding a higher speed node.
 
5.45 said:
Short barrel = faster powder, IMO
My 16.5 works well at 2550 fps with 38.8 gr Varget, 120 gr ELD-M
Click to expand...
I've had good results with Varget ,My hunting load 123 sst ,36.8 is shooting around. 7.8 .

The N150 groups anything.
I also have n560( faster ) I could try.

What's more suitable for the shorter barrel. Light,medium or heavy bullets.
 
What is the purpose of the ifle?

If it is for shooting groups at 100, you are off to a good start.

If you want to shoot targets at 300 to 1000 yards, or hunt, you need a slower powder that will get you around 2600 to 2700 fps.

Powders to try are Reloader 17 40 gr

IMR 4351 42 gr

H4350 42 gr
 
100 yard groups for now,though the range will be expanding next spring.
So far I've used n150,target,and h4350.
N150 the best ( but slowest) followed by Varget,then 4350.
I have n560 available as well.

I think I'm going to try the150 again, start6at 36 and work up.
Vithatori has 4 loads for the 130 g bullit and 150.
With the lowest starting point being 27 g ,for barnes TSX.
The other 3 all start at 32 g and up.

I think that's where I went wrong, by using the TSX data.
As I wasn't sure what bullit to compare my elders to.
 
5.45 said:
Short barrel = faster powder, IMO
Click to expand...

Popular myth, but it's incorrect. Scroll up to the QL chart, RL26 will give the highest velocity, whether the barrel is 16.5" or 26"



45C said:
I also have n560( faster ) I could try.

What's more suitable for the shorter barrel. Light,medium or heavy bullets.
Click to expand...

N560 is a slower burn rate, but will give more velocity than N150

Your rifle has a 1:8 twist barrel, it will stabilize anything really. In a 16.5" barrel, if higher muzzle velocity appeals to you, maybe stick to the 120gr class. If you're going to be pushing it past 500 yards, you'd be best with something very sleek in the 136+ grain , like the ELDm, Berger, Lapua Scenar. The 130gr ELDm you're shooting is decent, but designed for 2.8" OAL 260 Rem applications. The ogive is not near as sleek as the 140gr ELDm (G7 BC is .247 for the 130 ELDm, and .291 for the 140 ELDm)


If you didn't have any pressure signs at 36.0, I would suggest working up from there in 1% increments (0.4grs). Ladder up 36.4, 36.8, 37.2, 37.6grs. Shoot low to high, with the chrony. Stop if you hit 2500 fps with the 130gr ELDm / N150. If you need more velocity than that, I would switch to a different powder. The N560 comes to mind, although it will be a compressed load to get into the higher speed range
 
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