Thread: 300blk vs 6.5 grendel with short barrels

I will be building something similar after i finish my 6.5 build.

Short barrel 300blk in a MDT LSS with my Oceania Defence QD can on it.

I only really want it as a subsonic up close rifle, maybe with some super loads to get it to 150m. I think you have to pick what you want to use a rifle for for then make your decision on what the bullet can achieve. I think it will be hard to beat the 300blk in a short barrel around 10 - 12".

Below is sort of what I will be trying to emulate but with a buffer tube and Magpul CTR stock. Yep total vanity project.

I just can't work our who make the best 300blk bolt gun at the moment, @tikka has a Tikka t3x he got bored out to 300blk at 1:7 but I heard not many smiths here will do that for you now as the Tikka steel has proven it is so tough it is hard on their tooling.

I have been looking at the Howa and Rem 700 but also CZ does one as well that I heard is quite nice.

https://www.recoilweb.com/review-gea...ol-143737.html

Originally Posted by 308mate

I will be building something similar after i finish my 6.5 build.

Short barrel 300blk in a MDT LSS with my Oceania Defence QD can on it.

I only really want it as a subsonic up close rifle, maybe with some super loads to get it to 150m. I think you have to pick what you want to use a rifle for for then make your decision on what the bullet can achieve. I think it will be hard to beat the 300blk in a short barrel around 10 - 12".

Below is sort of what I will be trying to emulate but with a buffer tube and Magpul CTR stock. Yep total vanity project.

I just can't work our who make the best 300blk bolt gun at the moment, @tikka has a Tikka t3x he got bored out to 300blk at 1:7 but I heard not many smiths here will do that for you now as the Tikka steel has proven it is so tough it is hard on their tooling.

I have been looking at the Howa and Rem 700 but also CZ does one as well that I heard is quite nice.

https://www.recoilweb.com/review-gea...ol-143737.html

Attachment 136325

I was looking at a similar build (Howa 1500 SA, MDT chassis, buffer tube magpul furniture, even the ODL can) but .308 with a 14-16" barrel.

Originally Posted by dogmatix

I was looking at a similar build (Howa 1500 SA, MDT chassis, buffer tube magpul furniture, even the ODL can) but .308 with a 14-16" barrel.

Interesting. Those black collar arms pork sword things that Ken from 55six was/is going to bring in were saying they prefer the 308 over 300blk when I asked them last year.

I assume you dial the loads right down on the down them as the recoil would be pretty grunty on such a lightweight rifle on a full power 308 load.

I'm already doing a Tikka 16" 6.5 Creedmoor in a Carbon stock so would want to go to a very short 10 - 12" for the MDT build for something different, so will probably stick with 300blk as it seems the best round for that barrel length.

Hahaha I also have that same image as a template....

A good mate of mine an ex deer culler shoots deer out to 260m with his 300BLK running 194gr ME Lehigh’s subsonics and I can do it to 300m. It’s no different to long range hunting to a 1000m a well setup scoped rifle and the best reloading practice to get the best out of it. Adjust environmentals, angle and range for the ballistic app.
Lot of people go ohhhh you can’t do that type of hunting with subsonic rifles but a couple decades ago people were saying the same thing about shooting past 1K. Using the right projectiles for the required job help a lot too.

Another option is rebarrel a doner rifle to a short fast twist 308win, can then use heavy subs and run 125gr a lot faster than a 300 blackout.

This from one of my hunts a few years ago when I first got my 300BLK built.
FishnHunt - New Zealands Famous Hunting and Fishing Forum Since 1995 - Long range for a 300 blackout subsonic

Originally Posted by Vizsla

The 338BR will easy shoot subs pass 300m, it smashes anything over you hit, a super sized big big brother to a 300bkl

I’m waiting for the 8.6mm creedmoor to come out. I was looking at building a 338 whisper years ago but the 300BLK is better for high volume pest control. The good thing about 300 blackout the brass is easy to make or get. Many choices of projectiles for whatever job.

I think id go 308 if you wanted power at range
the kaimai concept that Dean maisy pushes holds a lot of water
its just a 308cal creedmore but it solves the difficulty feeding issues of the 300bkl and the seating length issue of the 308

fast twist in both will do subs as effectivly as a 300blk, honestly my 308 subs are just as quiet as 300blk subs

I find in normal rifles barrels going below 12 inches takes them below 762mm over all length

Originally Posted by berg243

is the grendel a barrel burner with short barrels and faster powders 14 inch and 16 inch. looking for an ultralight rifle with reasonable range 300m max but can work as a scrub rifle hence shorter barrel. was looking for peoples experience with grendel and 300blk as the 2 easy factory load options handloading later .never fireformed or resized brass just want a uncomplicated calibre.

I'm using a 20" Grendel, with some pretty stout loads, 120's @ 2550fps. The velocity and energy figures suggest it's good to 250-300m. Chopping one to 14-16" is taking it too far if you still want to use it out to those ranges. It becomes borderline when the impact velocities drop below 2000fps, and you'll struggle to get them starting out much above that if you lop it off too short.

Grendel isn't a barrel burner. Far from it. You get better barrel life than you would from a 308. I have used 85-90gr bullets with AR2219 and they grouped really well but more recently I got significantly better speed using BM2. The whole "if using a short barrel use fast powder" thing is a kind of a myth and BM2 and 8208 is right where it's at for 85-107 bullets, even in shorter tubes, H335 is close to BM2 and being ball powder helps avoid compressed loads. CFE223 will get the most speed out of 120gr+ bullets. Subs aren't worth it. The heaviest is a 160gr round nose and terminal performance will be non-existent if you can even get them to fit your mag, feed properly, and stabilise.

Plenty of people seem to get about 2300 or more with a 123gr ish bullet from short 11-12 inch Grendels - more than a 300BLK but also much more aerodynamic bullets.

Agree tikka 300Blk brass etc a lot easier to source, i had the 300 but the 338 is a huge setup in performance
300gr subs with 250gr or less supers

Yes my 24" Grendel (RIP black buddy) flung factory 123's SSTs @ 2550fps and I could emulate that with hand loads. @dogmatix got 2200fps from a 16 inch barrel so a 10-12 is likely to be slow. And forget subsonics, even if you get them to shoot ok they will only punch a 6.5 cal hole and unlikely to expand. 6.5 bullets are designed for super sonic speeds.
I would go 300BLK every time for such a short barrel. It uses fast rifle/shotgun powder and mine could fling 130s at 2200fps out of a 12.5" barrel so slightly more energy than dogmatix 6.5 with a 16". However I loaded it with Speer hollow points which expanded fine out to 200m on goats. Also it could shoot 200 - 240 grain subsonic projectiles which also worked fine at close range. Never stumped up and purchased Lehigh projectiles, cast lead holowpoints expand well enough.

Originally Posted by gimp

Plenty of people seem to get about 2300 or more with a 123gr ish bullet from short 11-12 inch Grendels - more than a 300BLK but also much more aerodynamic bullets.

I suspect they must be pushing it well beyond it's designed CPI.

Interesting though, reference?

https://forum.snipershide.com/thread...endel.6453095/


People claiming ~2300 or more with 123 factory ammo from 11.5-12.5 AR barrels

Unless you are running leighigh or subx bullets the subs i used on animals were not great. You need to head shoot with heavy match bullets and have the rifle zeroed for those bullets, it is ballistically a 45 ACP.

With supers I was shooting goats at 450m and dropped heaps under 200m. The 110 vmax performs like traditional hunting bullet at BLK velocities.

I'm seriously considering another one based on a Howa mini with a DPT and chopping the barrel to minimum legal, i would run supers for hunting and subs for the kids plinking. I despise the MDT chassis as they are cold in the hand and have no fore end to grip, just my 2c.

Here is my data.

FACTORY AMMUNITION
LOAD BULLET WEIGHT (GR) AVERAGE VELOCITY (FPS) AVERAGE GROUP (MM)
REMINGTON OTM 220 1007 14
KATIPO 110 2257 23
HORNADY A-MAX 208 917 20
HORNADY V-MAX 110 2246 33
HANDLOADS Lilgun powder
PROJECTILE CHARGE (GR) AVERAGE VELOCITY (FPS) AVERAGE GROUP (MM)
CAST 186 GR 8 1086 50
CAST 186 GR 15 1775 32
HORNADY 110 GR V-MAX 19 2208 27
HORNADY 110 GR V-MAX 19.5 2249 35
HORNADY 110 GR V-MAX 20 2288 25

If howa made a SS 300blk with a standard weight or light weight barrel in the same twist rate as their porky blued ones id definitely have one
its just not worth turning down the barrel or dealing with a blued rifle
they just need a good stock and the floorplate that seems to be on the way