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+--- Thread: 20" vs 24" Barrel? (/showthread.php?tid=21872)
20" vs 24" Barrel? - ACDriverD15 - 08-20-2020
Hey Folks!
I'm new to the Grendel Horde. Seeking your incite from your experience....
20" vs 24" Barrel?
In theory (all things being the same), the 24" barrel will deliver more muzzle velocity and more energy than the 20" barrel. That being said, there will be a weight and length penalty. All this stuff is just theory to me as I just got my PSA 12" pistol build and haven't gotten a chance to put it together yet....
The 12" will be my primary "truck gun" so to speak. Looking to put together a long range rig for hunting. Currently looking at a Sanders complete upper for that but can't decide the length of barrel.
So.....from your experience, what are your thoughts? 20" vs 24"?
GO!
20" vs 24" Barrel? - mel - 08-20-2020
ACDriverD15 Wrote:Hey Folks!
I'm new to the Grendel Horde. Seeking your incite from your experience....
20" vs 24" Barrel?
In theory (all things being the same), the 24" barrel will deliver more muzzle velocity and more energy than the 20" barrel. That being said, there will be a weight and length penalty. All this stuff is just theory to me as I just got my PSA 12" pistol build and haven't gotten a chance to put it together yet....
The 12" will be my primary "truck gun" so to speak. Looking to put together a long range rig for hunting. Currently looking at a Sanders complete upper for that but can't decide the length of barrel.
So.....from your experience, what are your thoughts? 20" vs 24"?
GO!
unless u plan on target shooting really far 20 will do just fine , my 20" barrel has let me hit targets at 1820y , that being said with my supressor the barrel is basically 28" long and ive had no problems hiking the thing threw the brush , and a 24 would just be easier even , my 20 inch build with a 3 pound scope ontop of it wieghs 11.2 or 11.5 pounds
i personally wish i woulda gone 24 to start , but now ive got a 28" inch barrel on the way and im sure ill end up doing some hunting with it as well
20" vs 24" Barrel? - tdbru - 08-20-2020
you can get light weight 20" tubes (faxon gunner, sixfivearms) as well as heavy barrels at that length, but i have yet to see a lightweight off the shelf 24" tube. when i got my upper i picked a 24" tube. the barrel was heavy fluted. with scope the rig was at 10.75 lbs sans sling or magazine. good ballistics, but quite a load to tote around over hill and dale. i figure a 20" light weight barrel and lightweight upper parts to go with it, keeping the same scope and mount, i'll likely end up just a bit over 8 1/4 lbs or so. i figure i'll lose maybe 80 to 100 fps by reducing the barrel length by 4", depending upon load i'm using.
so i would suggest to look at your hunting style. do you shoot mainly out of stands? then 24" and 11lbs could be an advantage. do you spot and stalk, and have a lot of elevation changes when your hunting? then i'd suggest a lightweight 20" build. if you're young and in shape, then toting 11lbs through the mountains may not be a big deal for you either.
and what are you hunting? because bullet weights go from ~85gr. to 140gr. or more. and varmint bullets open up easier and at lower impact velocities than big game bullets. the max range you should shoot at game at, in my opinion, is the range where the impact velocity is down to the point where the bullet will still expand. if you shoot game at distances so far that the impact speed of the bullet is so low that the bullet fails to expand on impact, you'll just poke a 6.5mm hole through the critter and you'll have a long tracking job ahead of you. Now the minimum impact speed for expansion varies greatly among the various types of bullets.
on light weight varmint type bullets, figure about 20 to 25 fps per inch of barrel length change. for the big game bullets that weigh a bit more, probably 15 to 20 fps change per inch of barrel length change. rough estimate. and see what that gets for you for max hunting range. then decide about portability vs max range and make your choice.
one more thing, if it is within your budget, whether you get a 20" or a 24", get the best barrel (quality) you can budget for, as this makes a huge difference on repeatable accuracy, in my opinion.
have fun.
-tdbru
20" vs 24" Barrel? - biodsl - 08-20-2020
My favorite, light 20" barrel. https://riflebarrels.com/wp-content/uploads/ar740.pdf
20" vs 24" Barrel? - drewthebrave - 08-23-2020
If you plan to hunt with Hornady SST, it's capable of expansion at a velocity of 1800 FPS based on real world results. With my 18" barrel, that cartridge maintains that velocity past 400 yards. Technically, Hornady says the SST should expand as low as 1600 FPS, and an 18" barrel will hold that speed past 550 yards. Unless you're hunting near the limits of that distance, a 20" barrel ought to suit you well.
20" vs 24" Barrel? - VASCAR2 - 08-23-2020
Here is a list of the tested ammo by average velocity for each barrel length.
120 Grain HP BT PPU
16" 2392
18" 2455
20" 2480
24" 2559
110 grain FMJ PPU
16" 2510
18" 2570
20" 2614
24" 2683
123 grain A-Max Hornady
16" 2419
18" 2464
20" 2505
24" 2568
123 Grain SST Hornady
16" 2430
18" 2493
20" 2511
24" 2583
Hand Load 123 Grain Nosler CC, 31.0 grains CFE223, CCI 450
16" 2449
18" 2471
20" 2526
24" 2619
100 Grain FMJ Wolf
16" 2507
18" 2571
20" 2615
24" 2695
Hand Load 107 Grain SMK 28.5 IMR8208XBR, CCI 41 Hornady cases.
20" 2658
24" 2729
Here is the difference between the 18 barrel compared to the shorter 16 barrel which was slower with every load.
120 grain PPU HP BT
63 FPS difference
110 grain PPU FMJ
60 FPS difference
123 grain A-Max
45 FPS difference
123 grain SST
63 FPS difference
Hand load 123 grain Nosler CC
27 FPS difference
Wolf 100 grain FMJ Steel cased
64 FPS difference
Difference between 20 and 18 barrel 6.5 Grendel
120 grain PPU HP BT
25 FPS difference
110 grain PPU FMJ
44 FPS
123 grain A-Max
41 FPS difference
123 grain SST
18 FPS
Hand load 123 grain Nosler CC
55 FPS difference
Wolf 100 grain FMJ Steel Cased
44 FPS difference
20" vs 24" Barrel? - VASCAR2 - 08-23-2020
Here is the difference for the tested ammo going from 24" barrel to 20" barrel. These velocities were obtained using a Magnettospeed chronograph a few years ago. The PPU ammo tested was ammo prior to the recall with large rifle primers.
Difference between 24" and 20"
PPU 120 grain HB BT
79 FPS
PPU 110 grain FMJ
69 FPS
123 grain A-Max, Hornady
63 FPS
123 grain SST, Hornady
72 FPS
Hand Load 123 grain Nosler CC, 31.0 grains CFE223, CCI 450
93 FPS
100 grain FMJ Wolf
80 FPS
Hand Load 107 grain SMK 28.5 grains IMR8208XBR, CCI 41
71 FPS
20" vs 24" Barrel? - riuma - 08-23-2020
I bought the rifle I liked -in my case CZ- and lived with the tube length it had. I have two 6.5 Grendel CZ's now. Both are 24" and not hard to handle.~Riuma