20 inch barrel on a 270

[308mate]

anyone own a 270 with a shorter (around 20in) barrel? in the real world is there much difference in performance?
I fancy a Sako finlight and I already own a 270 but I'm wondering will the shorter barrel reduce the performance to the point were there is no advantage over a 308 or 6.5 etc

 

[Southern]

My Steyr M stutzen is about 100 fps slower than my 24 inch Mauser, but I also have a 22 inch .270. It is loud. You don't know if your rifle will lose 100 or 200 fps until you cut it.

 

[kenbro]

Last week i had the barrel on my .25 calibre cut from 24 to 20 inch. (Original speed was 3003fps.)
Lost 200 fps.
Extra 2/10ths grain of powder gave me another 117 fps and still room for a bit more if i want it.
Ken.

 

[tackb]

to be honest you'd be as well with a 308 if you are going that short (personally I think the 308 is a match anyway if you use the same bullet weights)

 

[NoIDeer]

I'm using a 20" barrelled Sako 85 in win 270. Hornady interlock 130 gn do around 2850 fps. Quickload suggests that I am losing 140 fps over a 24" barrel.

Very nice rifle to use but gives a nice muzzle flash in the dark and a big bang without a mod.

 

[ironmatt]

I have a sako 85 s/s with a 20" barrel in .270 and im pushing a 130grn gameking at 3150fps with 57.5grn of N160 so not even max load. no pressure signs or anything. that's from 3 different chronos. People get caught up with barrel length but even if you lost 200fps I don't think the deer are going to notice and ballistically will make no noticeable difference inside stalking ranges.

 

[Ranger22]

I use a 270 with a 20 inch barrel. Can still hit what i’m aimimg at at the distances I shoot.

 

[NoIDeer]

I have a sako 85 s/s with a 20" barrel in .270 and im pushing a 130grn gameking at 3150fps with 57.5grn of N160 so not even max load. no pressure signs or anything. that's from 3 different chronos. People get caught up with barrel length but even if you lost 200fps I don't think the deer are going to notice and ballistically will make no noticeable difference inside stalking ranges.

Interesting! Identical load and rifle except the bullet -300 fps???

 

[User00033]

I used a 20" .270 a while back. You can expect a MV loss of 150ish fps as per other comments above.

My experience was not a good one simply because the bloody thing was painfully loud. But that is the same for my 20" .243 if I am stupid enough to use it without the suppressor. My view is that if you are determined to use unsuppressed shortened barrels for powerful cartridges you are asking for hearing damage, especially if you are shooting in the woods. Not everyone will agree but bugger that I say do the sensible thing otherwise you will be contributing to the deafness thread in off topic in a few years time.

 

[ironmatt]

Interesting! Identical load and rifle except the bullet -300 fps???

I was quite sceptical at first. but tried it on 3 separate occasions with 3 different chronos. think the lowest reading I ever had was a spread of 3080-3100fps. certainly performs well!

 

[Druid]

Last week i had the barrel on my .25 calibre cut from 24 to 20 inch. (Original speed was 3003fps.)
Lost 200 fps.
Extra 2/10ths grain of powder gave me another 117 fps and still room for a bit more if i want it.
Ken.

I assume it it was a 25-06? What load are you using Ken?

 

[monarman]

Both my previous 270's were chopped to 20 inches... to accomodate a moderator. Never chronographed any of them because deer didn't care how fast the bullets were..... they couldn't out run them!!!..... don't worry about how fast your bullets are.... concentrate on how accurate they are and then test the trajectory at the ranges you intend to shoot.
My new barrel in 7x57 is 20 inches too...... I don't know how fast my bullets are and don't care.... I shoot to within the limits of myself and my rifle.

You still get good killing power with a 20 inch 270.... so go for it.

 

[kenbro]

I assume it it was a 25-06? What load are you using Ken?

Twas my 25-45. (Before cut) 90gr. GameKing x 25.2 RL7. Rem. 7 1/2 Primer. Lap. brass. 3003fps. After cut 2800 fps. from 25.2 grs.
Regards,Ken.
PS. After cut. 25.4 RL7 = 2917 fps.

 

[Claret_Dabbler]

I'd do it. Get a good load for a 140gr bullet. The moderator will fix the muzzle flash and noise problems.

 

[Sinistral]

I don’t see how a necked up .223 with under half the case capacity of a .270 burning a fast powder in a short barrel is relevant to the OP’s question.

Also, in every manual I have ‘57.5grs of Vit N160’ is way over maximum for the 130gr .270, so said performance is being bought at the expense of pressure. In 22” and 24” barrels 3050 fps was the best I could ever get at maximum recommended loads. That was using Vit N160 & N165, Norma 204, Rottweil R904 & R907, and 60gr loads in H4831 & IMR 7828. These powders go with the .270 so any drop below 22” will affect MV.

If I had to take a 20” barrel for use with a moderator then the .308 which burns medium-fast powders would to be the better option.

 

[ironmatt]

I don’t see how a necked up .223 with under half the case capacity of a .270 burning a fast powder in a short barrel is relevant to the OP’s question.

Also, in every manual I have ‘57.5grs of Vit N160’ is way over maximum for the 130gr .270, so said performance is being bought at the expense of pressure. In 22” and 24” barrels 3050 fps was the best I could ever get at maximum recommended loads. That was using Vit N160 & N165, Norma 204, Rottweil R904 & R907, and 60gr loads in H4831 & IMR 7828. These powders go with the .270 so any drop below 22” will affect MV.

If I had to take a 20” barrel for use with a moderator then the .308 which burns medium-fast powders would to be the better option.

I have always found the best load data to be from the powder manufacturer. viht list 58.0grn as max load for a 130grn on their website. like I said in my comment, mine is showing no signs of excess pressure whatsoever, groups incredibly and is giving me good performance. whats not to like.

 

[NoIDeer]

Also, in every manual I have ‘57.5grs of Vit N160’ is way over maximum for the 130gr .270, so said performance is being bought at the expense of pressure. In 22” and 24” barrels 3050 fps was the best I could ever get at maximum recommended loads. That was using Vit N160 & N165, Norma 204, Rottweil R904 & R907, and 60gr loads in H4831 & IMR 7828. These powders go with the .270 so any drop below 22” will affect MV.

If I had to take a 20” barrel for use with a moderator then the .308 which burns medium-fast powders would to be the better option.

58 gns is the max load for N160 with 130 gn Remington SP according to Viht. Don't know where you get your data from?
ironmatt is doing very well with his load.

 

[kenbro]

I don’t see how a necked up .223 with under half the case capacity of a .270 burning a fast powder in a short barrel is relevant to the OP’s question.

Was just a way of showing that nobody can tell how many fps per inch you will lose when you shorten a barrel to a particular length. Irrespective of calibre.
Ken.

 

[Sinistral]

58 gns is the max load for N160 with 130 gn Remington SP according to Viht. Don't know where you get your data from?
ironmatt is doing very well with his load.

Thankyou,as the internet isn’t my first port of call. Your link shows this maximum gets only 3080 fps from a 62cm/24.5 barrel - rather than a 51cm/20” stubby.

I’m quoting from the Speer #13 and #14 manuals, and Sierra V. Their load data is developed and tested in real rifles, and published as an authoritative data source for those prepared to pay for it. It’s a lot more specific, and accompanied by a detailed commentary on the cartridge, test conditions, caveats, and so on.
Their results chime closely with mine for so many calibres that I’ve come to rely on the bullet-makers manuals. They aren’t out to push particular powders & just print what their bullets got with brand X,Y, or Z on a comparative basis. These manuals also give a detailed guide to reloading so to me they are well worth the money.

I don’t trust generic results from powder manufacturers websites, nor have much faith in any information which is put up on-line for free. I remain a sceptic, sorry about that.

 

[243 fallow]

I have a sako 85 s/s with a 20" barrel in .270 and im pushing a 130grn gameking at 3150fps with 57.5grn of N160 so not even max load. no pressure signs or anything. that's from 3 different chronos. People get caught up with barrel length but even if you lost 200fps I don't think the deer are going to notice and ballistically will make no noticeable difference inside stalking ranges.

I've just looked at the viht load data and it says 58grns of n160 is the max load giving 3083fps from a 24.5ins barrel. I used to have a 20ins 270 and with 130grn and a maximum loads could only get around 2700 - 2750fps with n165. The best and most accurate load was 110vmax at around 3200fps.