270 Cut Carbine

What is the problem?

It is difficult if you don't have a hacksaw and the skill and means to finish the muzzle and crown and possibly remount a front sight. Is it against the law? No - as long as you stay over the legal minimum length you can cut a factory barrel. 18.5 inches for a semi auto. 18 inches for a manual action... and make sure you know how to legally measure the barrel length.
 
SC is pulling your chain.

The only real time issue you will have is a significant velocity decrease.

Look at 35-50 fps for each inch of barrel you cut off.

You will also be changing barrel harmonics, which might have either a positive or negative accuracy effect.
 
Someone tested this already, from 22 to 16".

https://www.gunmart.net/shooting-accessories/customising-and-tuning/270-calibre-barrel-reductions

Here's the relevant highlights:
Thus, reducing the barrel from 22 to 16” to see the velocity/energy change with all factory and reloads as I cut the tube down to size. I cut the barrel using a standard hacksaw and deburred the muzzle to stop restriction of the passing bullets and then checked five bullets at each length for an average result over the chronograph.
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The 140-grain Winchester Ballistic Silver Tip round was the most efficient, with only -126 fps velocity loss from 3017 fps to 2891 fps, for a final energy figure of 2599 ft/lbs at 16”; again, a nice and short rifle but still very deer legal. The 150-grain Norma load only lost -187 fps and had 2247 ft/lbs of energy at 16”, which will humanely dispatch any deer.
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126fps and 187fps over 6", or 21 and 31fps per inch.

The best reload was in fact the 140-grain Nosler ....velocity reduction was minimal at -156 fps...
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26fps/inch with that load...


My guess would be, going to a 18" barrel, you'd lose 100-150fps from a 22" barrel and 150-200fps with a 24" barrel. If losing that velocity isn't an issue, I say have at 'er! A 270win spitting a high BC 130gr at 2850fps is still carrying around 2100fps at 1200ft/lb of energy at 400yds.
 
guntech said:
What is the problem?

It is difficult if you don't have a hacksaw and the skill and means to finish the muzzle and crown and possibly remount a front sight. Is it against the law? No - as long as you stay over the legal minimum length you can cut a factory barrel. 18.5 inches for a semi auto. 18 inches for a manual action... and make sure you know how to legally measure the barrel length.
Click to expand...
Maybe I should have been clearer in the meaning of my question. What kind of velocity would be lost from 22 to 18.5
 
Depending on bullet weight maybe 150 f/s. But that is an individual rifle thing... some more than others... no set rule.
 
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