Range Report 6mm CM 20" bbl velocity

[mosin46]

hope this is the right place to ask this. and,yes,i have done as much on line research (rifle shooter,factory web sites etc) as i can find. i am wondering if anyone has any hands on re 6mm CM (or even 243 & other similar 6mm) from a 20' bbl. reason asking; got a 24" 6mm savage/criterion FS on here and going nowhere. thought about keeping it and chopping to 20'". the blinds and stands i hunt out of are tight and i have even spooked deer getting a 22" bbl into position. a 24" would just not work. factory published data is often suspect vs real world #s. from what i can see,the external ballistics would be acceptable (just) on game < 300 lb-smallish WT and hogs. out to about 300m,which is my max range to shoot at live game with any caliber. tx for any input.

 

[308Gunner]

They will work look in the Bolt Action section then go to 16”-18” inch guns. I don’t think a 6 Creed is in there but you will get an idea. Also look in the reloading section

 

[Boatninja]

My 16.5" 1/8'' criterion barrel shoots almost 200fps less than data printed on Hornady Match 108 gr boxes. I can ring a 12" plate at 600 yds consistantly. I don't know what that hits with power wise. I never shoot whitetails at long range due to uncertainties in accurate evaluation, mistaking a nubbin buck for a doe could mean the loss of big $$$ to the landowner.The reason for short barrel is the same, tight quarters in blinds and getting off quick out the truck window shots on predators.

 

[mosin46]

thanks guys. i was thinking factory data minus at least 150. my set up is savage/criterion as well. so,you are dropping 25ft/sec per inch or so. not bad really. if i went this direction would have to rent a chrono or buy a cheap one to confirm vel loss. would lose sellability of 24" bbl. so,setup would be marginal @ 300,i think. prob 2400 @ 300? yea,the nubbin buck as a doe has been a big problem for me in the past. have vowed to NEVER shoot anything that i think weighs <90lb. in fla and in a lot of places 90 is a average/fair sized animal.

 

[Scotch_egg]

6 Creedmoor barrel length versus muzzle velocity (31 to 17 inches)

6 Creedmoor barrel length and velocity 6 Creedmoor is rapidly rising in popularity among long range shooters. Combining an efficient case design with the wide range of excellent 6mm bullets, the 6…

rifleshooter.com

 

[FUNCTIONAL]

I just built a 18.5" 6creedmoor to test velocity and other things. If I can find some 6creed factory ammo around here I'll see what it chronos for you as well as what velocity I was getting in handloads.

I can tell you out of a 22" I was able to push a 107smk at 3085 just fine.

Wont get to the range until the 13th though so youll have to sit tight for a week or so.

 

[thesemperfidude]

Following. I’ve been thinking about cutting a 24” 6 creedmoor I’ve got down to 18-20”

 

[DeadeyeD’rick]

I’m running a Tikka with a Bartlein barrel cut to 19”. Running 115 DTAC Coates RBT with 42.7gr of H4350 is giving me right at 2900fps. I have not seen any pressure sign at 42.7.

 

[Dogsniper]

20” 243 Ackley
48gr rl26
105 amax

 

[FUNCTIONAL]

Little late posting the results BUT.

18.5" barrel
105 w/ 42.7gr H4350 @2975 (no pressure could go higher)
110 w/ 40.8gr H4350 @2853 (just starting to see primer edges get sharper, approaching max)
105 w/ 37.2gr AR-Comp @2999 (primer flat)
110 w/ 36.7gr AR-Comp @2914 (no pressure could go higher)
105 w/ 44.9gr H4831SC @2830 (no pressure could go higher)
110 w/ 44.9gr H4831SC @2831 (no pressure could go higher)

Didnt test for accuracy, this was just trying to find my max velocity per powder. H4350 out of these 3 is still probably the best choice but is boarder line less case fill than id prefer. the H4831sc gives great case fill but without QL i'm concerned not enough is being burnt before it exits the muzzle (I run suppressed 100% of the time and it would foul up real quick). AR-Comp gave great velocity for the charge but not nearly enough case fill, I'd suspect the sd/es to be high but have not tested anything further yet.

Given these results I'd probably end up with H4350, if I wasnt to run much suppressed id probably go H4831sc. Only tested AR-Comp because I have 24#s of it with nothing to use it on.