lancetkenyon
Well-Known Member
Most of you know the name Rich Sherman, as in Sherman Short Mag, and the Sherman line of long cartridges (think Ackley Improved on steroids).
Many of you might also know Eric Goss, of Axisworks LLC, the gunsmith/artist many of us know and have a man crush on.
Well, these two mad scientists have collaborated and built the first ever (and ONLY) rifle chambered in the 6 SST (Sherman Short Tactical). Based off the 6.5SS (Sherman Short) which is a slightly shortened version of the 6.5 SAUM with body taper blown out and a 40° shoulder. I have one, and know of a few other guys that do too, and the case design is phenomenal and very efficient.
Well, the 6.5SST was born off the 6.5SS case first. From the demand for a shorter case, and with a 30° shoulder for slightly easier feeding for the PRS crowd to push the 140-150 upwards of 3100-3200fps, while fitting in a detachable mag with the long bullets. Well, naturally, for even less recoil to be able to see your own hits (or misses), the thought of a 6mm version was conceived to push a 105-115 to near 3200fps with lower pressure and better brass life than the 6CM, 6x47L, 6XC with max loads will allow.
So Eric built his second PRS rifle, and chambered the very first 6SST in existence. This big fat pig weighs in at 22lbs 9oz all in. Crazy, right? Well, there is a method to his madness. Weight=recoil absorption. This rifle kicks like a sub-sonic .223.
R700SA DBM
MPA (Masterpiece Arms) RAT (Rapid Adjustment Technology) chassis w. about 8lbs of weights installed, fully adjustable cheek piece and LOP, barracade stop, vert grip
27" Benchmark 1:7.5" MTU contour w. 5 port self-timing Muscle Mag brake
Trigger Tech Special @ 1#
Atlas Bipod
AIAX magazine w. Axisworks +2 base
Badger Ordinance 20MOA Picatinny rail
USO 34mm rings
Vortex Razor Gen II 4.5-27×56 w. EBR-2C MIL
I started load development on this rifle/cartridge combo. Rich Sherman has brass from Norma and ADG available. I have some of both. They are within 9gr of each other. They do take a bit of work to prep. They start out as a .300SAUM or 6.5SST brass depending on what type you get.
Neck it down from 7mm or 6.5mm to 6mm
FL size
Expanding mandrel
Neck turn
Anneal
Load
The SST takes a lot less fire forming than the SS version, since it retains the 30° shoulder and only slightly alters case taper and shoulder/neck.
Here is a loaded round, ready for fire forming. Rich states the SST fire forming loads can be run at full loads since forming to chamber is minimal.
So I loaded up 10 sighters and a 23 round ladder test, and not knowing where starting load might be. Rich and I talked about what we thought might be a good starting load. Being a totally new cartridge, we hoped we were on the right track.
Eric and I discussed uses and hopes for this round. Eric chose what bullet he wanted to try, and we knew what primer to use. He let me pick a powder, one that is clean burning, temp stable, fairly slow burning, and would have good case fill. H1000 seemed to fit the bill. Not the fastest speeds from it, but with a 3200fps cap.on speeds for PRS, that should be very attainable. We also decided to see what we could hit for a future hunting rifle build too.
Took it out to the desert and zeroed it at 100 to 1.5" high.
Cold clean bore shot was the right, then 4 more right at the top of the diamond. These were mid-range loads, 3256fps average w. 110 SMK @ .0200" jump.
Out to 200 to verify in preparation for the ladder test. That shows some promise!
The winds were really whipping today. 18mph L-R w. gusts. Then swirling later to 10+ R-L. Making wind holds impossible. So I just shot holding center. 343 yard ladder test. I would have gone further, but I had a good depression to lay in to help limit wind blowing on me.
Here are the results of the ladder test....
We definitely hits speeds better than Rich and I were expecting with H1000.
Next will be charge weight testing followed by seating depth testing.
The rifle should be a real shooter when load development is complete. I am honored to be the first person to ever work on a load for this new cartridge and another amazing Axisworks rifle.
To be continued.....
Many of you might also know Eric Goss, of Axisworks LLC, the gunsmith/artist many of us know and have a man crush on.
Well, these two mad scientists have collaborated and built the first ever (and ONLY) rifle chambered in the 6 SST (Sherman Short Tactical). Based off the 6.5SS (Sherman Short) which is a slightly shortened version of the 6.5 SAUM with body taper blown out and a 40° shoulder. I have one, and know of a few other guys that do too, and the case design is phenomenal and very efficient.
Well, the 6.5SST was born off the 6.5SS case first. From the demand for a shorter case, and with a 30° shoulder for slightly easier feeding for the PRS crowd to push the 140-150 upwards of 3100-3200fps, while fitting in a detachable mag with the long bullets. Well, naturally, for even less recoil to be able to see your own hits (or misses), the thought of a 6mm version was conceived to push a 105-115 to near 3200fps with lower pressure and better brass life than the 6CM, 6x47L, 6XC with max loads will allow.
So Eric built his second PRS rifle, and chambered the very first 6SST in existence. This big fat pig weighs in at 22lbs 9oz all in. Crazy, right? Well, there is a method to his madness. Weight=recoil absorption. This rifle kicks like a sub-sonic .223.
R700SA DBM
MPA (Masterpiece Arms) RAT (Rapid Adjustment Technology) chassis w. about 8lbs of weights installed, fully adjustable cheek piece and LOP, barracade stop, vert grip
27" Benchmark 1:7.5" MTU contour w. 5 port self-timing Muscle Mag brake
Trigger Tech Special @ 1#
Atlas Bipod
AIAX magazine w. Axisworks +2 base
Badger Ordinance 20MOA Picatinny rail
USO 34mm rings
Vortex Razor Gen II 4.5-27×56 w. EBR-2C MIL
I started load development on this rifle/cartridge combo. Rich Sherman has brass from Norma and ADG available. I have some of both. They are within 9gr of each other. They do take a bit of work to prep. They start out as a .300SAUM or 6.5SST brass depending on what type you get.
Neck it down from 7mm or 6.5mm to 6mm
FL size
Expanding mandrel
Neck turn
Anneal
Load
The SST takes a lot less fire forming than the SS version, since it retains the 30° shoulder and only slightly alters case taper and shoulder/neck.
Here is a loaded round, ready for fire forming. Rich states the SST fire forming loads can be run at full loads since forming to chamber is minimal.
So I loaded up 10 sighters and a 23 round ladder test, and not knowing where starting load might be. Rich and I talked about what we thought might be a good starting load. Being a totally new cartridge, we hoped we were on the right track.
Eric and I discussed uses and hopes for this round. Eric chose what bullet he wanted to try, and we knew what primer to use. He let me pick a powder, one that is clean burning, temp stable, fairly slow burning, and would have good case fill. H1000 seemed to fit the bill. Not the fastest speeds from it, but with a 3200fps cap.on speeds for PRS, that should be very attainable. We also decided to see what we could hit for a future hunting rifle build too.
Took it out to the desert and zeroed it at 100 to 1.5" high.
Cold clean bore shot was the right, then 4 more right at the top of the diamond. These were mid-range loads, 3256fps average w. 110 SMK @ .0200" jump.
Out to 200 to verify in preparation for the ladder test. That shows some promise!
The winds were really whipping today. 18mph L-R w. gusts. Then swirling later to 10+ R-L. Making wind holds impossible. So I just shot holding center. 343 yard ladder test. I would have gone further, but I had a good depression to lay in to help limit wind blowing on me.
Here are the results of the ladder test....
We definitely hits speeds better than Rich and I were expecting with H1000.
Next will be charge weight testing followed by seating depth testing.
The rifle should be a real shooter when load development is complete. I am honored to be the first person to ever work on a load for this new cartridge and another amazing Axisworks rifle.
To be continued.....
