data-csrf="1711719405,b0090c7af2d7f254f0ba511b576d75aa" M7 Saum to? | As Real As It Gets

M7 Saum to?

Calvin

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Nov 17, 2007
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Thinking of rebarreling a M7 7 Saum to a 6.5 variety.

Without going DBM, would a 6.5 PRC or 6.5 Saum work given the magbox of the M7? Or is it a horrible idea.
 

Big Stick

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Nov 18, 2007
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The quicker you run from the Seven,the sooner you'll be money/time ahead.

What excatly is it,that you are hoping to do?...................
 

Big Stick

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I'd MUCH prefer a Kreedmire with a 147 ELD M and .697 BC,for the (4) grains of mass trade awat from .625 BC's. 'Course it's a shorter case too,which "lengthens" the mag box.

I've got 1000's of 143's,but the 147 stands alone and the Kreed can't squirt 'em fast enough,to get in a pickle.

Win/win/win.................
 

Big Stick

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Distance is mechanical,wind is Voodoo...if only as per always.

BC do many things and most are in a hurry to look at it all wrong,which I rather enjoy. Extrapolation is key and it's never not intellesting to compare/contrast fps of impact velocity lost,per (1) yard of distance and how many inches of drift are incurred,for every (1) mph of wind.

I personally weigh impact velocity and drift,a bunch more than a whole fucking bunch. for distant ZipCodes,the Transonic distance matters muchly too.

Wanna fuck with heads?!? Simply extrapolate a "lowly" 21" 7-08 and 180 ELD's at 2600fps. Then think recoil,grains of powder,barrel life,round count in magazine,etc...........
 

Big Stick

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If only as an opener.



300yds costs 308fps and every (1) mph of full value wind is a .4" shift.
500yds costs 502fps and every (1) mph of full value wind is a 1.16" shift
700yds costs 687fps and every (1) mph of full value wind is a 2.37" shift
1000yds costs 949fps and every (1) mph of full value wind is a 5.2" shift.

Right at (1) fps of velocity loss,for every yard(as a gross average),is a rather nice place to be and that wind drift be a touch friendly.

Less than 42grs of powder.......................
 
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Big Stick

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6.5 PRC/143 ELD X at 3100fps.




300yds costs 427fps and every (1) mph of full value wind is a .4" shift.
500yds costs 696fps and every (1) mph of full value wind is a 1.16" shift
700yds costs 949fps and every (1) mph of full value wind is a 2.4" shift
1000yds costs 1299fps and every (1) mph of full value wind is a 5.35" shift.

Wind shadows the 7-08/180,but velocity loss is of course greater. Costs at least (1) round in the belly,more recoil,more barrel length,greater rifle weight and 59grs of powder.

Food for thunking..................
 

Big Stick

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7 ShamWow/180 ELD M,with PRC length barrel at 2800fps.




300yds costs 320fps and every (1) mph of full value wind is a .36" shift.
500yds costs 524fps and every (1) mph of full value wind is a 1.04" shift
700yds costs 718fps and every (1) mph of full value wind is a 2.12" shift
1000yds costs 991fps and every (1) mph of full value wind is a 4.63" shift.

59grs of powder...............
 

Al Nyhus

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Dec 30, 2008
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Thinking of rebarreling a M7 7 Saum to a 6.5 variety. Without going DBM, would a 6.5 PRC or 6.5 Saum work given the magbox of the M7? Or is it a horrible idea.
Yes to your last sentence! ;)

Other than moving to a 700...which does have some big upsides...I can't think of a single reason to change your Model 7. -Al