7 Sherman Short COAL

BoomFlop

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Wisconsin
Curious as to what you COAL is on the 7 SS with a 180 Berger Hybrid? I loaded a dummy round at 2.900" (2.151" CBTO) as that should be approximately .020" off the lands with a standard .110" reamer per Rich.

Did you use standard reamer with .110 throat or did you have it throated out more? My action is a Kelbly Atlas Tactical and Accurate WSM mags. What is max length to reliably feed from a WSM mag?

Thanks all,
Steve
 
Throated both mine out .065", coal was 2.987" my cbto was 2.262". In both my bbls the 180 hybrid shot best between .030-.036" off. They feed fine out of the accurate 300 wsm mags however I'm running the Hawkins flush in mine
Did you use a ptg unithroater? Just curious. I have a 7ss that's not been fired. .110fb. I thought about throating for 190s but there's probably no turning back to 180s after it's throated that long.
 
Yes that's what I used. Built a dummy and went a little at a time until I got desired touch. The 180 hybrid seems like a great all around bullet to throat for. Still works great w 175's and 180 vlds. Not sure you'd see any advantage running the 190's over the 180's unless you just have a ton of them. Here is a before and after.. I didn't measure coal after throating but you can get good idea from OAL before throating and the comp (cbto) measurements after to get an OAL for all the bullets I found touch for

AC9C15E0-90B2-4A79-A7F0-41A1135AD685.jpeg
 
Mine is cut with a standard 7SS reamer from Rich.
I am running the 184 F Open Hyb @ 2.210" CBTO, 2.977" COAL to just fit in the WSM mag. That leaves me with a .068" jump.
A 180 Hyb @ 2.210" CBTO is 2.944" COAL. Still at .068" jump. You could go out another 030" to 2.974" and fit in a WSM mag, and only be at .038" jump.
 
Mine is cut with a standard 7SS reamer from Rich.
I am running the 184 F Open Hyb @ 2.210" CBTO, 2.977" COAL to just fit in the WSM mag. That leaves me with a .068" jump.
A 180 Hyb @ 2.210" CBTO is 2.944" COAL. Still at .068" jump. You could go out another 030" to 2.974" and fit in a WSM mag, and only be at .038" jump.
Did you buy the reamer from Rich and confirmed it's .110" freebore? Not trying to start an argument but your numbers don't jive from what everyone else has found for touch (2.920ish) with the 180 hybrid. Your numbers look to be more freebore than .110". Maybe I'm not understanding what you wrote, are you saying 2.944" is .068 off the lands so touch is 3.012"?
 
@elkaholic (Rich)

Do you use the standard .110 reamer on all your 7 SS's or do you add extra freebore? I know you also use the Accurate WSM mags and want to take advantage of the case, while fitting in the mag with room to load longer as throat burns out as well over time.

Thoughts and recommendation would be greatly appreciated.

Thanks
Steve
 
@elkaholic (Rich)

Do you use the standard .110 reamer on all your 7 SS's or do you add extra freebore? I know you also use the Accurate WSM mags and want to take advantage of the case, while fitting in the mag with room to load longer as throat burns out as well over time.

Thoughts and recommendation would be greatly appreciated.

Thanks
Steve
.110 is used the most because it covers several bases well. that said, there is nothing wrong with adding some FB if you
have mag room, and you usually do with a good SA DBM
 
Rich (@elkaholic)

I have 1000 180 gr Berger Hybrids and that is going to be my primary bullet for this rifle. What advantage would adding additional freebore provide and what would you recommend that freebore be with the Accurate WSM mag?

Thanks,
Steve
 
Did you buy the reamer from Rich and confirmed it's .110" freebore? Not trying to start an argument but your numbers don't jive from what everyone else has found for touch (2.920ish) with the 180 hybrid. Your numbers look to be more freebore than .110". Maybe I'm not understanding what you wrote, are you saying 2.944" is .068 off the lands so touch is 3.012"?
The reamer is what my gunsmith has, and has built all the 7SS with. So I don't know his exact FB.
This weekend, I will double check where actual CBTO is with a 180 Hyb, since I will be loading up some 169 HH to try out anyway, and will need to find CBTO to lands with that bullet. I will verify and post up numbers for 169 HH, 180 Hyb, and 184 F Open Hyb then.

I know my stated measurements of what I am running are 100% correct, I will doublecheck jump however.
 
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I am really leaning on staying with the standard .110. Be interested to see what you come up with Lance. I know your comparator as well as bullet lot will be slightly different, however, still be interesting.

I'm really thinking of staying with standard freebore and trying Erik Cortina's seating depth method to find the node.

Thanks all,
Steve
 
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