7mm x 55 Swedish????

[mikegaiz]

Has anyone ever tried a 7mm x55 Swedish? looking for a little more oomph than a 7mm x 47 Lapua. Need accuracy and good brass and barrel life. I know there was a 7.5mm x 55 but not so great performance. Any other ideas? Target is 7mm 168 gr. to 178 gr. bullets to 1000yds.

mike

 

[2644ever]

Try the 7x57 Ack Imp or the .284 Winchester.

 

[mikegaiz]

Has anyone tried s 7mm WSSM?

 

[Laurie]

7mm WSSM would give similar performance to 7mm-08 assuming that the bullet wasn't seated too deep in the case - which it would be in a WSSM dedicated action to reduce the COAL enough.

7X55mm (based on 6.5X55) wouldn't offer any benefit over 7X57mm, and would have considerably less performance than 7X57AI.

Water capacity in grains weight is as follows for the various cases:

6.5X55 ..... 57
7X54R ....... 58
7X57 ......... 59.5
7X57AI ..... 62.4
7.5X55 ..... 65
.284W ...... 66

7X54R is the necked down 7.62X54R, a potent sporting cartridge used in Finland when 7.62X54R was outlawed for sporting shooting after WW2 for some years. (Or 7X53R / 7.62X53R as the Finns call this pair.)

The 7.5X55mm Swiss GP11 is a superb cartridge and very potent in a modern bolt-action allowing higher than CIP pressures to be employed. Despite the 7.5mm label it is a true .30 Cal, and can of course be necked down to 6.5 or 7mm. Brass might be an issue, although Norma and RWS make it.

However with the .284 Win having slightly more case capacity than the 7.5 and a fair bit more than the others, good brass readily available, and a proven track record, it's difficult to see any good reason for not making it the first choice in a mid capacity 7mm. Reamers, dies and all the rest are available off the shelf too.

If I were looking to develop a rarely seen and effective small to mid size wildcat, I'd have a go at .270-08. P O Ackley described it as a great little cartridge and couldn't understand why it had never been developed and adopted by the large manufacturers.

Laurie,
York, England

 

[David2011]

Why 7mm? The beauty of the 6.5x55 is the very high ballistic coefficients. Look up a ballistic calculator and compare the retained energy and drop of the 6.5mm bullets compared to 7mm or .308 bullets at comparable velocities. OK, give the bigger bullet a head start with a 200-300 fps advantage. Downrange the 6.5 will probably be going faster and carrying more energy as the less efficient bullets bleed off their speed. I am a big 6.5mm fan and built a 6.5x55 on a Mauser 98 action. M96s are too pricey to build into hunting rifles these days. I can shoot 60 rounds of 6.5x55 at one sitting and not hurt the next day. The Europeans shoot 6.5x55 at 1000 yards- or is it metres?

David

 

[acloco]

I use 284 Winchester brass in all three of my Swiss K31 rifles. Neck up to 30 cal, load and go.

7x57 would be your best bet if staying with 7mm/.284 caliber.

280 Rem is a possibility as well.

As the last poster advised, the 6.5/.264 bullets are the way to go. High BC and SD.