6.5 cm 2500 fps to slow?

dastt

dastt

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So I just chrono'd my 6.5cm and it seems a little slow

The load is:

38.4gr h4350
139gr lapua scenar
Hornady brass
Federal primers

I don't have the proper comparator so I used the 6mm one, I measured to my lands, turned out to be 2.845" w/ the 6mm comparator, I found the rifle likes a 0.020" jam. Accuracy is under 2" @ 300m, and over the chrono I was +/- 8fps at 2500fps so it was really consistent.


I'd like to shoot further, am I where I need to be or should I try hotter? During testing I went up to 43gr but was not impressed at all.
 
How were the pressures at 42 gr and what kind of speed ? Maybe playing with the OAL will settle things down a 20 thou jam smells like vertical to me.
I have never seen to many other than light 22 bullets benefit from being jammed some but who knows, my best results when doing load development have been to start about 5-10 thous off the lands .
 
dastt said:
So I just chrono'd my 6.5cm and it seems a little slow

The load is:

38.4gr h4350
139gr lapua scenar
Hornady brass
Federal primers

I don't have the proper comparator so I used the 6mm one, I measured to my lands, turned out to be 2.845" w/ the 6mm comparator, I found the rifle likes a 0.020" jam. Accuracy is under 2" @ 300m, and over the chrono I was +/- 8fps at 2500fps so it was really consistent.


I'd like to shoot further, am I where I need to be or should I try hotter? During testing I went up to 43gr but was not impressed at all.
Click to expand...

That is slow but you are only using 38.4 grs. Also don't know your rifle, barrel length etc. I am using 42.3 grs of H4350 with 139 Scenars at 20 thou jump out of an AI AX, 26"AINA Bartlein bbl and getting an average of 2830 fps. It is a very accurate load with no pressure signs using Hornady brass. I am on the 5th firing with some lots and still going strong.
 
It's out of a Ruger precision rifle, sorry I meant to say 20 thou jump not jam.

Pressure was fine at 42, maybe I'll retry, I didn't have the comparator so off the hop I didn't want to sink with it so I loaded them at COL of factory Hornady ammo.
 
With 4350 you should be able to get another 100-150 fps with that load.

I feed my creed H414 (because I have it/use it with other calibers). Only piddled around with 140 Accubonds for a bit, but was getting about 2600'ish with 40 grains - didn't push it beyond that (I don't load hot), but ultimately now load 130 grain Scirocco's because I plan on using the rifle for hunting.

I use the "relatively tame" Nosler data and it shows you could go up to 41 grains of H4350 (41.5 for IMR 4350) and still be below max - as long as it still groups for you of course :)
 
Had same problem, didn't realize the Hornady 5 piece comparator set didn't come with 6.5/264; should've bought the 14 piece set.
6mm should work with quality bullet with consistent ogive curve.

Def. do the 2 shot ladder, working up to max to see if the rifle will perform at higher velocity.

Need to do same for my CTR 260 Rem. Only had enough powder for one 5 shot group at 39.7grs H4350. Def. can do 1/2moa grouping.
dastt said:
...
I don't have the proper comparator so I used the 6mm one, I measured to my lands, turned out to be 2.845" w/ the 6mm comparator ...
Click to expand...
 
I did the 2 shot ladder up to 42, and it was far worse at 42gr.

38.5gr both shots were nearly touching, while 42 was nearly 3" of all vertical.

I'm going to redo the test with proper 0.020" and see what that changes
 
"38.5gr both shots were nearly touching, while 42 was nearly 3" of all vertical." seems like something more than powder.

I'm also using 139gr lapua scenar, Federal primers but new Lapua brass (went with 260 for Lapua brass). The necks were super tight, couldn't seat the bullets using wilson die, mini arbor. Had to i/s chamber, then run all the new brass through the expander ball. Didn't have to do that with Lapua 308 brass. Yeah, too lazy to COW the new brass.

New brass, xFired? prepping?
 
My friend and I got into 6.5's this time last year. I went with the 260 and he went with the Creedmoor. The CM load is 140 Amax over 41.8gr of H4350 in Hornady brass. We clocked them at 2780 and the groups are small. The upper node for most 6.5's is around 2800 fps. My upper node on the 260 with 139 Scenars is at 2830fps.

I should mention that both of our barrels are 1:8 and finished around 22"

My best guess, if you didn't have pressure signs at 42, I would load 41.3, 41.8, 42.1 and 42.4. I bet you find your winner in there somewhere
 
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