Thread: A whim...

could try the 17 bergers Tahr?

Originally Posted by Tahr

Yeah. The only thing is that the 270wsm isn't suited to a shorter barrel, where-as I could go to 22"-20" with the 7SAUM and still get pretty good performance with 150 grn.

The 270wsm is threaded so I might get a DPT 7mm suppressor for it and see how unwieldy it makes it. I'm not interested in a brake.

You should still reach 3000fps with 150's and Retumbo/2225 in a 22" barrel. That's where mine is running with a DPT on the end and I wouldn't be worried about cutting it down to 20" if I felt I wanted it shorter.

Originally Posted by southernman

Yep, that's the real joke on all the .270 haters, that then say get a 7mm, most aren't bright enough to know, and those that do, are just pissed that the 270 win has thrashed the .280 and .284, in sales volumes by 100-1 or more for 60 years.

Actually.... I couldn't give a toss about sales volume, if you follow the masses as a policy you tend not to be

bright enough to know

...... I do however care about projectile choice. There are some options available now for the 270, but you have to ask the question .... if the 270 actually kills in sales, why don't the projectile manufacturers develop for it? And the answer is.... it used to kill in sales (but no more), and its limited in cartridge case options to either the 270 Win or the 270 WSM and thats about it....

If projectile choice improves then its right in the zone of 6.5-7mm for high BC projectiles @ 120-160gr which is all we need to effectively deal with real life hunting requirements in this country, without having the recoil, noise and weight issues created by high BC options in 30 cal and above....

I was going to pick that rifle up too @thar.. am keen to do a 6.5 SAUM.... but might have ended up doing exactly the same and using it as is.... lol the LRAB looks OK...

Originally Posted by Gibo

could try the 17 bergers Tahr?

What do you mean by "17" Gibo?

Originally Posted by Tahr

What do you mean by "17" Gibo?

ha chuck a 0 on the end

Why would the WSM be any worse with a short barrel than the SAUM?

Larger case should provide more velocity loaded appropriately in any barrel length.

Originally Posted by veitnamcam

Why would the WSM be any worse with a short barrel than the SAUM?

Larger case should provide more velocity loaded appropriately in any barrel length.

I think its to do with efficiency and expansion ratios. The ratio between the bullet diameter and powder capacity dictates how efficient a combination is. By efficient I mean the loss of velocity per inch of barrel and per grain of powder. e.g. the 25-06 is less efficient than a 30-06, thus requires a longer barrel to achieve optimal performance.

The WSM has a smaller bullet diameter and larger case capacity when compared to the SAUM. So in terms of efficiency, the SAUM wins.

The same with the 22.243 and the .223. When both fired out of a 20" the 22.243 uses a heap more powder to get a similar outcome.

So, if you start hacking the 270WSM barrel you are soon back to 270W performance, but using 10 grns more powder, getting more blast, more bang, and more barrel wear.

I made most of that up, but I think that's how it works.

Originally Posted by Tahr

I think its to do with efficiency and expansion ratios. The ratio between the bullet diameter and powder capacity dictates how efficient a combination is. By efficient I mean the loss of velocity per inch of barrel and per grain of powder. e.g. the 25-06 is less efficient than a 30-06, thus requires a longer barrel to achieve optimal performance.

The WSM has a smaller bullet diameter and larger case capacity when compared to the SAUM. So in terms of efficiency, the SAUM wins.

The same with the 22.243 and the .223. When both fired out of a 20" the 22.243 uses a heap more powder to get a similar outcome.

So, if you start hacking the 270WSM barrel you are soon back to 270W performance, but using 10 grns more powder, getting more blast, more bang, and more barrel wear.

I made most of that up, but I think that's how it works.

Well yes but the wsm should be faster and if you were worried about efficiency rather than speed you would use a 7mm08 or neck up a 223 that would be efficient as

If you want shorter and was thinking of rebarreling anyway why not hacksaw (if you have nothing better that is) a few inches off it and see what can be achieved, not like a second hand 270 barrel has a huge resale value.

Originally Posted by veitnamcam

Well yes but the wsm should be faster and if you were worried about efficiency rather than speed you would use a 7mm08 or neck up a 223 that would be efficient as

And theres nothing wrong with that

Originally Posted by Tahr

I think its to do with efficiency and expansion ratios. The ratio between the bullet diameter and powder capacity dictates how efficient a combination is. By efficient I mean the loss of velocity per inch of barrel and per grain of powder. e.g. the 25-06 is less efficient than a 30-06, thus requires a longer barrel to achieve optimal performance.

The WSM has a smaller bullet diameter and larger case capacity when compared to the SAUM. So in terms of efficiency, the SAUM wins.

The same with the 22.243 and the .223. When both fired out of a 20" the 22.243 uses a heap more powder to get a similar outcome.

So, if you start hacking the 270WSM barrel you are soon back to 270W performance, but using 10 grns more powder, getting more blast, more bang, and more barrel wear.

I made most of that up, but I think that's how it works.

Think you are dead right @Tahr in your theory but the difference in bore volume between the .277 and .284 bore is negligible and overall capacity (case and bore) can be managed with the speed of the powder. As long as you don't need to shoot heavier bullets than they make in 270 I'm not sure it will make much difference.