dwever
Member
I read some posts today on a thread started in August issuing unnecessary caution about Scandium frames. The ole, "Carry a lot, shoot a little." And so forth.
1. I hope from the information below including from S&W and Buffalo Bore, we might put some Scandium issues in perspective. I own both a Scandium framed M&PR8 and TRR8, and bought my first Scandium S&W in 2008.
2. Since the real challenge around using the lighter Scandium framed weapons surrounds Bullet Creep, I'll look specifically at what that is, how it happens, and how to test for it.
3. Finally, I'll conclude that given the >35 oz. weight of the current production N Frame Scandium .357's with steel cylinders, there's really nothing to worry about including bullet creep. Shoot whatever as much as you want.
CALLING S&W PC: I decided to give the Performance Center a call, and I talked to two guys about putting the big heavy stuff in my scandium weapons, and the message was essentially if it is in SAAMI specs, shoot it. I specifically asked the second guy about the Buffalo Bore 1,700 FPS (in 5" barrel) High Velocity and Heavy loads that pack 800 ft. lbs. Response was, if it's in SAMMI and you can take it, it won't hurt the weapon. Well it went through my 586 L-Comp fine, so no worries; and, I would later learn from Tim Sundles at Buffalo Bore that that particular ammo is indeed SAMMI spec (he also provided me a link).
READING BUFFALO BORE: What does BB think about their Heavy High Velocity big loads in S&W lightweight revolvers. Quote (MY CAPS): "THE AMMO ITSELF WON'T HURT THESE SUPER LIGHT WEIGHT REVOLVERS. These revolvers are simply so light that the recoil is severe enough to cause crimp jump." And it is strictly on the basis of crimp jump, not damage to the lightweight frames that BB says, "We don't recommend this ammo to be fired in super light alloy revolvers as bullets may jump crimp under recoil." But for the big scandiums, those loads if SAAMI Spec are fine. Why? Because there is a HUGE difference between a .357 Magnum in a 13.8 ounce M&P 340 J frame (or an 11.7 ounce 360 PD) and a 36 oz. M&P Scandium N Frame. In the big 36 ounce Scandium N Frame you have over 300% more mass to mitigate the revolver jerking backwards when fired than with the 11.7 ounce J Frame.
WHAT EXACTLY IS CRIMP JUMP & BULLET CREEP: For those unfamiliar with crimp jump, or what some call bullet creep, it is simply when after firing some cartridges in a cylinder, the remaining cartridge(s) in the cylinder have become longer because of the big recoil. As that recoil jerks the revolver back towards the shooter it acts as a kinetic bullet puller, because that heavy bullet wants to stay put as the gun snaps/recoils back. It is the sameish physics that allow you to snap your wrist and shake a thermometers' temperature down - if you could shake your wrist violently enough holding a round by the rim, you could make enough centrifugal force to force the bullet out of the cartridge right? That is roughly what the recoil is doing. The cartridge is suddenly snapping backwards pulling massive amounts of G's, while the heavier bullet is saying, "I can't pull that many G's with you without coming out of the cartridge a little." So to mitigate this you must mitigate the G forces, and this can be done with a heavier weapon. Even in Scandium, an N frame M&PR8 is already a heavier weapon weighing only one ounce less than a 37 ounce Stainless Steel 627 UDR N Frame; while a 360 PD is only 11.7 ounces. It is the latter class of micro weight guns that Buffalo Bore is warning about in this caliber.
APPLICATION for this discussion: super light revolvers can suffer from crimp jump, but the frames will be fine if SAMMI spec'd bullets are used. What are the chances of crimp jump happening in a 35 oz. TRR8 or 36 oz. M&P R8 with hotish .357 Magnum? Virtually none. What about creep or jump in say a 23 oz. 327 Scandium Pug or an S&W Scandium 25 oz. 329 PD .44 Magnum shooting full house loads? I haven't tested that and don't want to! It just takes the physics to another level with the principles remaining constant; in the case of the Scandium .44 Magnum 329 PD, you have with some ammo the recoil of 1,280 ft. lbs. of energy applied to a 25 oz. weapon.
HOW TO TEST FOR CREEP OR JUMP: But if you're still worried, get your hottest loads, put a Sharpie dot on one bullet, fire all chambers but the dotted one, then inspect the dotted bullet for jump or creep. Then, put the dotted one back in the cylinder, load the other chambers again, you get it. So I fired 49 American Eagle .357 Magnums (539 Ft. Lbs.) through my TRR8 with the dotted bullet staying in it's chamber unfired each time, and at the end of 49 rounds the bullet remained fully seated. Not my hottest load, but I wanted a $25 dollar test not a $50 one.
A WORD ABOUT SAMMI SPECS AND WHY A HANDFUL OF COMPANIES OCCASIONALLY IGNORE THEM: These specs generally reflect old data on metal fatigue, and the resulting maximum pressures SAMMI allows causes some manufacturers like BB to occasionally find the dated specs ridiculous because modern guns and the steel they're manufactured from can withstand sometimes double the pressure prescribed by SAMMI. At the same time, BB insists that their biggest loads in .357 can be used in any modern .357, but with some of the really light weapons, recoil snap may be so severe as to loosen bullets from their crimp. I tend to use Federal Premium for hunting anyway; they're always within SAAMI, and after all, I hunt in the S.E. where game size and danger is limited.
So, with the blessings of the Mother Ship and one of Her food suppliers, I'm just going to continue to shoot everything from my TRR8 and M&P R8 in copious amounts like I've done all along with my 627's and the 586 L-Comp. Peace.
1. I hope from the information below including from S&W and Buffalo Bore, we might put some Scandium issues in perspective. I own both a Scandium framed M&PR8 and TRR8, and bought my first Scandium S&W in 2008.
2. Since the real challenge around using the lighter Scandium framed weapons surrounds Bullet Creep, I'll look specifically at what that is, how it happens, and how to test for it.
3. Finally, I'll conclude that given the >35 oz. weight of the current production N Frame Scandium .357's with steel cylinders, there's really nothing to worry about including bullet creep. Shoot whatever as much as you want.
CALLING S&W PC: I decided to give the Performance Center a call, and I talked to two guys about putting the big heavy stuff in my scandium weapons, and the message was essentially if it is in SAAMI specs, shoot it. I specifically asked the second guy about the Buffalo Bore 1,700 FPS (in 5" barrel) High Velocity and Heavy loads that pack 800 ft. lbs. Response was, if it's in SAMMI and you can take it, it won't hurt the weapon. Well it went through my 586 L-Comp fine, so no worries; and, I would later learn from Tim Sundles at Buffalo Bore that that particular ammo is indeed SAMMI spec (he also provided me a link).
READING BUFFALO BORE: What does BB think about their Heavy High Velocity big loads in S&W lightweight revolvers. Quote (MY CAPS): "THE AMMO ITSELF WON'T HURT THESE SUPER LIGHT WEIGHT REVOLVERS. These revolvers are simply so light that the recoil is severe enough to cause crimp jump." And it is strictly on the basis of crimp jump, not damage to the lightweight frames that BB says, "We don't recommend this ammo to be fired in super light alloy revolvers as bullets may jump crimp under recoil." But for the big scandiums, those loads if SAAMI Spec are fine. Why? Because there is a HUGE difference between a .357 Magnum in a 13.8 ounce M&P 340 J frame (or an 11.7 ounce 360 PD) and a 36 oz. M&P Scandium N Frame. In the big 36 ounce Scandium N Frame you have over 300% more mass to mitigate the revolver jerking backwards when fired than with the 11.7 ounce J Frame.
WHAT EXACTLY IS CRIMP JUMP & BULLET CREEP: For those unfamiliar with crimp jump, or what some call bullet creep, it is simply when after firing some cartridges in a cylinder, the remaining cartridge(s) in the cylinder have become longer because of the big recoil. As that recoil jerks the revolver back towards the shooter it acts as a kinetic bullet puller, because that heavy bullet wants to stay put as the gun snaps/recoils back. It is the sameish physics that allow you to snap your wrist and shake a thermometers' temperature down - if you could shake your wrist violently enough holding a round by the rim, you could make enough centrifugal force to force the bullet out of the cartridge right? That is roughly what the recoil is doing. The cartridge is suddenly snapping backwards pulling massive amounts of G's, while the heavier bullet is saying, "I can't pull that many G's with you without coming out of the cartridge a little." So to mitigate this you must mitigate the G forces, and this can be done with a heavier weapon. Even in Scandium, an N frame M&PR8 is already a heavier weapon weighing only one ounce less than a 37 ounce Stainless Steel 627 UDR N Frame; while a 360 PD is only 11.7 ounces. It is the latter class of micro weight guns that Buffalo Bore is warning about in this caliber.
APPLICATION for this discussion: super light revolvers can suffer from crimp jump, but the frames will be fine if SAMMI spec'd bullets are used. What are the chances of crimp jump happening in a 35 oz. TRR8 or 36 oz. M&P R8 with hotish .357 Magnum? Virtually none. What about creep or jump in say a 23 oz. 327 Scandium Pug or an S&W Scandium 25 oz. 329 PD .44 Magnum shooting full house loads? I haven't tested that and don't want to! It just takes the physics to another level with the principles remaining constant; in the case of the Scandium .44 Magnum 329 PD, you have with some ammo the recoil of 1,280 ft. lbs. of energy applied to a 25 oz. weapon.
HOW TO TEST FOR CREEP OR JUMP: But if you're still worried, get your hottest loads, put a Sharpie dot on one bullet, fire all chambers but the dotted one, then inspect the dotted bullet for jump or creep. Then, put the dotted one back in the cylinder, load the other chambers again, you get it. So I fired 49 American Eagle .357 Magnums (539 Ft. Lbs.) through my TRR8 with the dotted bullet staying in it's chamber unfired each time, and at the end of 49 rounds the bullet remained fully seated. Not my hottest load, but I wanted a $25 dollar test not a $50 one.
A WORD ABOUT SAMMI SPECS AND WHY A HANDFUL OF COMPANIES OCCASIONALLY IGNORE THEM: These specs generally reflect old data on metal fatigue, and the resulting maximum pressures SAMMI allows causes some manufacturers like BB to occasionally find the dated specs ridiculous because modern guns and the steel they're manufactured from can withstand sometimes double the pressure prescribed by SAMMI. At the same time, BB insists that their biggest loads in .357 can be used in any modern .357, but with some of the really light weapons, recoil snap may be so severe as to loosen bullets from their crimp. I tend to use Federal Premium for hunting anyway; they're always within SAAMI, and after all, I hunt in the S.E. where game size and danger is limited.
So, with the blessings of the Mother Ship and one of Her food suppliers, I'm just going to continue to shoot everything from my TRR8 and M&P R8 in copious amounts like I've done all along with my 627's and the 586 L-Comp. Peace.
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