maximum barrel length gains

[onlybrowning]

I am in the process of getting an Encore Pro Hunter in .30-06. This is a 28" barrel. I am wondering how much increase over a 24" barrel I will see.

Rob

 

[Ridgerunner665]

20 to 30 fps per inch at most...15 to 20 fps at least.

 

[normo]

The good news is the longer barrel will still feel (handle) the same or better than a bolt rifle due to the break open action.
Maximum velocity potential in a package the same length or shorter.
Can't go wrong with a T/C....

 

[Big Squeeze]

I am in the process of getting an Encore Pro Hunter in .30-06. This is a 28" barrel. I am wondering how much increase over a 24" barrel I will see.

Rob

.........................Ridgerunner is about right on the money!

I own a 16.5" barreled 300 WSM Ruger Frontier and compared my chrony results to two 24" 300 WSM`s owned by friends using the same identical reloads; powders, bullets, OAL`s, primers, cases, trim lengths, everything the same.

Depending on the load, my average velocity loss vs the 24`s averaged anywhere from between 14.4 fps to 18.6 fps per inch. A total overall loss of between 108 fps up to 139.5 fps for a barrel 7.5" (31%) shorter or roughly a total loss of 3.5% to 4.5% overall. Loads were performed with 150 & 180 grain bullets. However those results are for the 300 WSM.

A 3.5% to 4.5% overall velocity loss, from a barrel 31% shorter than a 24 inch.

Based on the porportion of my results, I`ll take a guess that your overall velocity percentage gain with a 28" barreled 30-06 over a 24" er, will be around 2% to 3%, given the same identical reloads.

As another reference, I duplicated a Jeff Quinn reload found on his site (2/6/07; archives section) at "gunblast.com" for my 20" 375 Ruger Alaskan. For the exact same duplicate reload, the velocity given for his test rifle, a 23" 375 Ruger African, exceeded my Alaskan by 67 fps, or a difference of 22.3 fps per inch.

Dick Metcalf also tested a 16.5" tubed 7mm/08 Ruger Frontier (shootingtimes.com, "long gun" section). The difference between the Frontier and a 24" 7mm/08 he tested, was 16.4 fps per inch using the same factory ammo.

 

[Ridgerunner665]

Yep...when you go past 24 inches, you reach the point of diminishing returns.

Going from a 20 inch to a 24 will get you around 50 fps per inch...then going from 24 to 28 you will get around 20 fps....from 28 on, you will get less and less the farther you go.

Some rounds are more affected by shorter barrels than others...the more "over bore" a round is the more you will gain with a longer barrel.

For example...a 308 gains very little from 20 to 24 inches (about 30 fps per inch...if that much), but a 243 gains around 90 fps per inch with 100 grain bullets (on average)

The "short mags" kinda play by their own rules...they are designed around efficiency of powder burn....However, the same rules do still apply, but the difference in velocity between barrel lengths may not be so much.

 

[fjlee]

I am in the process of getting an Encore Pro Hunter in .30-06. This is a 28" barrel. I am wondering how much increase over a 24" barrel I will see.

Rob

I used QUICKLOAD to get a theoretical number. It says that the difference with 30-06, between 24" and 28" , is 100 fps total. I used my elk load with 180 gr bullet in my calcs. Other /06 loads would probably have VERY slight variations on this 100 fps figure.

Lee in Denver CO

 

[Antelope_Sniper]

Yep about 16 to 50 fps depening on case and powder selection. You will see a larger gain with slower powders, and more "overbore" cartridges. Biq Squeezes experiences are usually very different then mine, but then again, we shoot at opposite ends of the spectrum.

 

[hvy barrel]

I tested the difference between a 308 with a 20" barrel & one with a 26" barrel. Using the same box of ammo in both rifles. The velocity difference was about 45fps.

 

[Big Squeeze]

I tested the difference between a 308 with a 20" barrel & one with a 26" barrel. Using the same box of ammo in both rifles. The velocity difference was about 45fps.

...........Was that difference 45 fps per inch OR a total of 45 fps overall????

If it is a 45 fps difference overall, then I like that much better!!!

45 fps divided by the 6" difference in barrel length= only 7.5 fps per inch!!

That difference is really a closer than expected difference!..... Wow!....I like it!......I wish my results were that close.

 

[Guy Miner]

For several years I shot the same ammo out of a 24" .308 and a 30" .308 Win. Both were Krieger barrels.

The ammo churned up 2850 fps from the 24" barrel, and about 2980 fps from the 30" barrel for a difference of about 130 fps in the 6" longer tube.

 

[Big Squeeze]

For several years I shot the same ammo out of a 24" .308 and a 30" .308 Win. Both were Krieger barrels.

The ammo churned up 2850 fps from the 24" barrel, and about 2980 fps from the 30" barrel for a difference of about 130 fps in the 6" longer tube.

..........21.66 fps per inch...... Right on par.

 

[hvy barrel]

I tested the difference between a 308 with a 20" barrel & one with a 26" barrel. Using the same box of ammo in both rifles. The velocity difference was about 45fps.

...........Was that difference 45 fps per inch OR a total of 45 fps overall????

If it is a 45 fps difference overall, then I like that much better!!!

45 fps divided by the 6" difference in barrel length= only 7.5 fps per inch!!

That difference is really a closer than expected difference!..... Wow!....I like it!......I wish my results were that close.

That was the total difference. I was shooting factory Hornady 168gr Amax match ammo.
The rifles were a Rem 700 PSS 26" barrel & a Rem 700P LTR 20" barrel.

I am pretty sure that you could have a bigger difference with different powders, but I have not tried that myself yet.

 

[onlybrowning]

I am not really a fan of long barreled guns for hunting, as I hunt with a 22" barreled A bolt in .270 and a 23" barreled A bolt in .325 WSM. The 28" TC barrel is a Pro Hunter barrel, so it is fluted. Might look funny if I have it cut down...but I might do it anyway.

Rob

 

[FOTIS]

Ridgerunner and normo are dead on. I messed with my buddy's TC in 25-06 (bull barrel mind you) and felt like a standard bolt 22" barrel rifle.