NEW 7 SHERMAN SHORT TACTICAL (SST)

[Aaronfields]

I have a 7ss. Like RR79 said if you have the room go SS. If not go SST. You can always use less than max loads in the SS and achieve the same velocity as the SST.

Regards,

I have a defiance tenacity cutout for Wyatt or I'll just use magazines I haven't decided

 

[SteelBanger]

I'm going to resurrect this thread ... and possibly be the first to start reporting some 7 SST data? My barrel is still probably 4 weeks out but I have dies and brass on hand, and all other components on the way. This is what I'll be starting with:

ADG 7 SST head stamped brass
Federal GM210M primers
H1000 (about all I could find right now, if / when I see some RL26 or N565 i'll try those as well)
Berger 180gr hybrids

The rifle will be a Terminus Zeus action with a 24" 1:8 Proof Sendero CF barrel from Straight Jacket Armory, sitting in an XLR Magnesium Element 3.0. I think the last 2 things I need to grab are a magazine and some scope rings, and I plan to put an Area 419 Hellfire brake on it at some point also. Any recommendations on a quality magazine?

Rich, what's a good starting point and rough idea on max for H1000? And for future reference, do you have a drawing of the case specs? Max case length and min trim length or should trimming not really be necessary with this cartridge?

 

[elkaholic]

I'm going to resurrect this thread ... and possibly be the first to start reporting some 7 SST data? My barrel is still probably 4 weeks out but I have dies and brass on hand, and all other components on the way. This is what I'll be starting with:

ADG 7 SST head stamped brass
Federal GM210M primers
H1000 (about all I could find right now, if / when I see some RL26 or N565 i'll try those as well)
Berger 180gr hybrids

The rifle will be a Terminus Zeus action with a 24" 1:8 Proof Sendero CF barrel from Straight Jacket Armory, sitting in an XLR Magnesium Element 3.0. I think the last 2 things I need to grab are a magazine and some scope rings, and I plan to put an Area 419 Hellfire brake on it at some point also. Any recommendations on a quality magazine?

Rich, what's a good starting point and rough idea on max for H1000? And for future reference, do you have a drawing of the case specs? Max case length and min trim length or should trimming not really be necessary with this cartridge?

case capacity. 70.5
H1000 210 primer
start at 58
Max approx 63-64*
Oal is 1.960
trim to 1.950"

What FB did you go with?

 

[SteelBanger]

case capacity. 70.3
H1000 210 primer
start at 58
Max approx 63-64*
Oal is 1.960
trim to 1.950"

What FB did you go with?

Thank you Rich, I'll start at 58 and go up to 64 in .5 increments and see if/when I hit the max for my rifle. Straight Jacket said they'd call to talk about the chamber setup once they get to my barrel so I haven't heard from them yet on that. With the 180 hybrid bullet, should I request anything specific for the freebore?

 

[elkaholic]

Thank you Rich, I'll start at 58 and go up to 64 in .5 increments and see if/when I hit the max for my rifle. Straight Jacket said they'd call to talk about the chamber setup once they get to my barrel so I haven't heard from them yet on that. With the 180 hybrid bullet, should I request anything specific for the freebore?

With a 3" mag, I might go up to . 175" FB but if you only have 2.950" the std . 110
FB reamer will be fine.

 

[SteelBanger]

With a 3" mag, I might go up to . 175" FB but if you only have 2.950" the std . 110
FB reamer will be fine.

I'm pretty sure I'll be limited to the 2.95" so I'll have them stick with the standard reamer, thanks again Rich! Hopefully I'll have some data to report around mid-July.

 

[elkaholic]

I'm pretty sure I'll be limited to the 2.95" so I'll have them stick with the standard reamer, thanks again Rich! Hopefully I'll have some data to report around mid-July.

The .110" works very well with a lot of loads.
I had a guy this week shooting the180 at 3051' with RL26 with a 26" barrel .

 

[SteelBanger]

Hey Rich I just stumbled onto a keg of RL26, what would be my starting load and rough max for the 7SST with 180gr hybrids?

It sounds like I should have my barrel from SJA sometime next week so I'm going to start by loading up ladders in .5 increments with H1000 and RL26 to find my max charge and see what kind of speed I can pull out of her.

Also, what's a safe COAL to load these ladders at? Once I get some fired brass I'll get a modified case made up so I can measure my CBTO and figure out my length to the lands.

 

[elkaholic]

Hey Rich I just stumbled onto a keg of RL26, what would be my starting load and rough max for the 7SST with 180gr hybrids?

It sounds like I should have my barrel from SJA sometime next week so I'm going to start by loading up ladders in .5 increments with H1000 and RL26 to find my max charge and see what kind of speed I can pull out of her.

Also, what's a safe COAL to load these ladders at? Once I get some fired brass I'll get a modified case made up so I can measure my CBTO and figure out my length to the lands.

Good deal!

I would start at 55 RL26 to fire form and max with formed brass would probably be 60 grains, give or take a grain.
H1000 needs about 3 grains more for equal pressure so start about 57-58.
Safe coal with a 180 hybrid I would load about 2.890"
What barrel and length?

 

[SteelBanger]

Good deal!

I would start at 55 RL26 to fire form and max with formed brass would probably be 60 grains, give or take a grain.
H1000 needs about 3 grains more for equal pressure so start about 57-58.
Safe coal with a 180 hybrid I would load about 2.890"
What barrel and length?

Thanks Rich, it's a 24" Proof CF Sendero.

So should I run all 200 of my cases at those starting loads to fire form, and then work up the ladders to max pressure? Will they be fully formed after the first firing or should I wait to make a modified case until after the 2nd firing to ensure the case is good to go?

 

[elkaholic]

Thanks Rich, it's a 24" Proof CF Sendero.

So should I run all 200 of my cases at those starting loads to fire form, and then work up the ladders to max pressure? Will they be fully formed after the first firing or should I wait to make a modified case until after the 2nd firing to ensure the case is good to go?

One firing is good enough but I would not run max until you do. I hope you dont have problems with that Proof barrel. We've had a bunch lately!!

 

[SteelBanger]

One firing is good enough but I would not run max until you do. I hope you dont have problems with that Proof barrel. We've had a bunch lately!!

Yeah I've been reading some threads about them and it's got me a little nervous, fingers crossed!!

 

[Jakeweb09]

Curious if anyone has any real world data on the 7sst yet? I've been shooting 7 Saum but looking to build a shorter rig with a 20-22" bbl. I've got plenty of h1000 and rl26 to go with.

 

[SteelBanger]

Curious if anyone has any real world data on the 7sst yet? I've been shooting 7 Saum but looking to build a shorter rig with a 20-22" bbl. I've got plenty of h1000 and rl26 to go with.

I hope too real quick. A couple issues set my build back quite a bit but I'm hoping to get it out to shoot the week after Christmas. I'll just be breaking the barrel in and fire forming so I won't have full velocity info for a while still unfortunately but I'll keep this thread updated as I go.