6.5 SS and 137 Hammer Hunter

[parshal]

Is anyone running this combo? I'm guessing the throat may need lengthening given the 1.557" bullet length. If so, what load have you settled on?

I've been testing the 124 (really 126 gr) hammers and they shoot very well. I came across a 7 twist Proof carbon and want to try the 137's.

 

[lancetkenyon]

I will be building a new 6.5SS 1:7.5" this fall, and this is one of my two planned hunting loads to work up.
Anxious to see if anyone has experience too.

 

[cjl2010]

Steve sent me a couple to check seating depth. I was touching lands right at 2.86 in my SS. With 124s (126) I touch at 2.735.

With my 7 twist I might have to grab some 137s and see how they fly. It's not close enough to hunting season to load the 124s or else I'd go broke

 

[parshal]

126's in mine are 2.313" at the lands with a Hornady comparator.

 

[parshal]

I wanted to follow up on this. With the Hornady 6.5 comparator I hit the lands at 2.331" with the 137's. The longest I can fit in my Wyatt's magazine is 2.288". So, I'm .043" off the lands at magazine depth.

I'm going to shoot some test loads tomorrow.

 

[Korhil78]

Well how did they shoot?

 

[RockyMtnMT]

I think we had some issues with stability. Seems to come one go from rifle to rifle. These long for caliber bullets are tough. Looks like e may have to redesign this one with a little shorter nose and longer bt to move the weight forward a bit.

 

[parshal]

I spoke with Steve after my session and his summary above is what I found.

I loaded H1000 and R23 each with five charge weights in .5" grain increments. I reached 3184 with R23 before pressure signs. I reached 3117 with H1000 before pressure. Each of those powders had one bullet hit sideways at 250 yards. I'd hoped for more velocity as well.

 

[Edd]

This testing was done with a 7" twist barrel?

 

[RockyMtnMT]

This testing was done with a 7" twist barrel?

7 twist proof. 6000' ish elevation. This indicates that it is a dynamic stability issue not ballistic stability. We'll see what we can do with design.

 

[parshal]

This testing was done with a 7" twist barrel?

Yes. Density altitude was 6049'.