woferry
Well-Known Member
Hi, I get the concept of the spacers, and having only flown AT DMS motors (which sure are easy, but also very limited choices) and 2 AT reloads that I had to borrow cases for, I'm interested in purchasing some cases of my own, and really like the idea of the spacers to reduce the number of cases I have to buy and carry around. I'm particularly interested in the CTI system because of the larger selection of reloads in each diameter/case size, though I'll ask the same question about AeroTech reloads in a separate thread (as their case options are much more confusing to me than CTI's).
But what I am less certain about are the "rules" for the various sizes. For CTI I think I have a reasonable grasp on how it works, but I'm hoping somebody 'in the know' can confirm or correct these statements (feel free to comment on as much or as little as you know for certain, i.e. first-hand experience):
29mm: There are 7 total case sizes, 1-6G and 6GXL. It appears in this size that the 6GXL is effectively a "7G" length, and uses the standard spacer to handle 6G reloads. So in this size I believe there is only a 'standard' spacer, which can take a 3G down to a 1G, 4G to 2G, 5G to 3G, 6G to 4G, and 6GXL to 5G, each using 2 standard spacers (and one size up each with a single spacer of course).
Right now (just FYI in case anybody else cares), my tally of reloads available for each 29mm case size (using BAR's current store list) is as follows: 1G: Fx7; 2G: Gx7; 3G: Gx6, Hx6; 4G: Hx8; 5G: Hx6; 6G: Hx7, Ix1; 6GXL: Hx2, Ix2 (52 reloads total: Fx7, Gx13, Hx29, Ix3).
38mm: Again 7 total case sizes, 1-6G and 6GXL. This time the 6GXL isn't effectively a "7G", it appears to be even longer than a 7G would be. So there is both a 'standard' spacer and an 'XL' spacer, and to adapt a 6GXL down to 6G reloads you use both the XL spacer and a standard spacer. Once again the sizes go 3G->1G, 4G->2G, 5G->3G, 6G->4G and 6GXL->5G, though there are 3 total spacers in this last one, 2 standards plus an XL spacer (this seems to break the "2 spacers max" rule, but is shown on the second page of https://www.pro38.com/pdfs/Pro38_Case_Spacer.pdf, so they seem to be okay with it in this case). This means if you buy the 6GXL case you'll want two standard spacers and one XL spacer to get the most use out of it.
Right now, my tally of reloads available for each 38mm case size is as follows: 1G: Gx9; 2G: Hx9; 3G: Hx1(Vmax), Ix9; 4G: Ix8; 5G: ix5, Jx7; 6G: Jx6; 6GXL: Jx9 (63 reloads total: Gx9, Hx10, Ix22, Jx22).
54mm: Same theme on the cases, 1-6G and 6GXL. Here it seems the 6GXL isn't quite one grain-length longer, if CTI's drawings are to scale the XL spacer in this size appears to be shorter than the standard spacer. The same size adaptations apply: 3G->1G, 4G->2G, 5G->3G, 6G->4G and 6GXL->5G, the last one using one XL spacer and one standard spacer this time. This means if you buy the 6GXL in this size it only makes sense to buy one standard spacer and one XL spacer, not 2 standards like with the 38mm cases, assuming the 3 spacers that are allowed with the 38mm cases is not allowed here (or else the 6GXL could adapt all the way down to 4G reloads). In fact it seems like you don't need two standard spacers in the 54mm line, as if you get the 6GXL, 4G and 2G cases with a single standard and one XL spacer you should be able to cover all 7 reload sizes with the fewest number of parts(?).
Right now, my tally of reloads available for each 54mm case size is as follows: 1G: Ix6; 2G: Ix1, Jx9; 3G: Jx8, Kx1; 4G: Kx11; 5G: Kx10; 6G: Kx8; 6GXL: Kx2, Lx7 (63 reloads total: Ix7, Jx17, Kx32, Lx7).
75mm & beyond: I guess there are no spacers for these larger motors, you need the appropriate case for the reload you buy. I didn't count the reload options above 54mm as I'm not expecting to go beyond a 54mm mount just yet.
I think I've also read that some CTI case sizes are compatible with AeroTech reloads (I think this includes 54mm and perhaps larger)? Is there a mapping of what CTI case matches which AeroTech case? Is it an unwise idea to consider the use of spacers even if mixing cases and reloads is an option here? If it's not an issue, presumably you'd want to use the AeroTech Reload Adapter System with an AeroTech reload in an oversized CTI case (since you'd need AT's Floating Forward Closure)? If it is an issue, this certainly might influence which cases you'd want to buy if there were "interesting" AT reloads that would be compatible with that CTI case.
It's a bit unfortunate that there are 7 cases per diameter when the spacers only cover 3, it means you need 3 cases and have some redundancy if you want every reload option, rather than being able to get by with only 2 (as if there were only 6 lengths per diameter, or if 3 spacers were allowed). But there are some instances where this probably works out, for example I'm not interested in the G motors that use the 38mm 1G case, so here I could just buy the 4G and 6GXL cases and 3 spacers (2 standard + 1 XL) and have a bunch of H, I & J motors to choose from (54 in total!).
As my first post here, I'm not sure whether I can edit it after the fact or not. If I can I can apply any corrections to the text above, so perhaps the top of this thread can serve as a reference.
Thank you in advance!
Will Ferry
NAR #96512, L1
TRA #15328, L1
L1: 9/2013, GLR T-Bolt "Thunderbolt" (R.I.P.), H148R, XPRS
Impulse flown: 2013: 767N, 2014: 4298N
Launches & Videos
But what I am less certain about are the "rules" for the various sizes. For CTI I think I have a reasonable grasp on how it works, but I'm hoping somebody 'in the know' can confirm or correct these statements (feel free to comment on as much or as little as you know for certain, i.e. first-hand experience):
29mm: There are 7 total case sizes, 1-6G and 6GXL. It appears in this size that the 6GXL is effectively a "7G" length, and uses the standard spacer to handle 6G reloads. So in this size I believe there is only a 'standard' spacer, which can take a 3G down to a 1G, 4G to 2G, 5G to 3G, 6G to 4G, and 6GXL to 5G, each using 2 standard spacers (and one size up each with a single spacer of course).
Right now (just FYI in case anybody else cares), my tally of reloads available for each 29mm case size (using BAR's current store list) is as follows: 1G: Fx7; 2G: Gx7; 3G: Gx6, Hx6; 4G: Hx8; 5G: Hx6; 6G: Hx7, Ix1; 6GXL: Hx2, Ix2 (52 reloads total: Fx7, Gx13, Hx29, Ix3).
38mm: Again 7 total case sizes, 1-6G and 6GXL. This time the 6GXL isn't effectively a "7G", it appears to be even longer than a 7G would be. So there is both a 'standard' spacer and an 'XL' spacer, and to adapt a 6GXL down to 6G reloads you use both the XL spacer and a standard spacer. Once again the sizes go 3G->1G, 4G->2G, 5G->3G, 6G->4G and 6GXL->5G, though there are 3 total spacers in this last one, 2 standards plus an XL spacer (this seems to break the "2 spacers max" rule, but is shown on the second page of https://www.pro38.com/pdfs/Pro38_Case_Spacer.pdf, so they seem to be okay with it in this case). This means if you buy the 6GXL case you'll want two standard spacers and one XL spacer to get the most use out of it.
Right now, my tally of reloads available for each 38mm case size is as follows: 1G: Gx9; 2G: Hx9; 3G: Hx1(Vmax), Ix9; 4G: Ix8; 5G: ix5, Jx7; 6G: Jx6; 6GXL: Jx9 (63 reloads total: Gx9, Hx10, Ix22, Jx22).
54mm: Same theme on the cases, 1-6G and 6GXL. Here it seems the 6GXL isn't quite one grain-length longer, if CTI's drawings are to scale the XL spacer in this size appears to be shorter than the standard spacer. The same size adaptations apply: 3G->1G, 4G->2G, 5G->3G, 6G->4G and 6GXL->5G, the last one using one XL spacer and one standard spacer this time. This means if you buy the 6GXL in this size it only makes sense to buy one standard spacer and one XL spacer, not 2 standards like with the 38mm cases, assuming the 3 spacers that are allowed with the 38mm cases is not allowed here (or else the 6GXL could adapt all the way down to 4G reloads). In fact it seems like you don't need two standard spacers in the 54mm line, as if you get the 6GXL, 4G and 2G cases with a single standard and one XL spacer you should be able to cover all 7 reload sizes with the fewest number of parts(?).
Right now, my tally of reloads available for each 54mm case size is as follows: 1G: Ix6; 2G: Ix1, Jx9; 3G: Jx8, Kx1; 4G: Kx11; 5G: Kx10; 6G: Kx8; 6GXL: Kx2, Lx7 (63 reloads total: Ix7, Jx17, Kx32, Lx7).
75mm & beyond: I guess there are no spacers for these larger motors, you need the appropriate case for the reload you buy. I didn't count the reload options above 54mm as I'm not expecting to go beyond a 54mm mount just yet.
I think I've also read that some CTI case sizes are compatible with AeroTech reloads (I think this includes 54mm and perhaps larger)? Is there a mapping of what CTI case matches which AeroTech case? Is it an unwise idea to consider the use of spacers even if mixing cases and reloads is an option here? If it's not an issue, presumably you'd want to use the AeroTech Reload Adapter System with an AeroTech reload in an oversized CTI case (since you'd need AT's Floating Forward Closure)? If it is an issue, this certainly might influence which cases you'd want to buy if there were "interesting" AT reloads that would be compatible with that CTI case.
It's a bit unfortunate that there are 7 cases per diameter when the spacers only cover 3, it means you need 3 cases and have some redundancy if you want every reload option, rather than being able to get by with only 2 (as if there were only 6 lengths per diameter, or if 3 spacers were allowed). But there are some instances where this probably works out, for example I'm not interested in the G motors that use the 38mm 1G case, so here I could just buy the 4G and 6GXL cases and 3 spacers (2 standard + 1 XL) and have a bunch of H, I & J motors to choose from (54 in total!).
As my first post here, I'm not sure whether I can edit it after the fact or not. If I can I can apply any corrections to the text above, so perhaps the top of this thread can serve as a reference.
Thank you in advance!
Will Ferry
NAR #96512, L1
TRA #15328, L1
L1: 9/2013, GLR T-Bolt "Thunderbolt" (R.I.P.), H148R, XPRS
Impulse flown: 2013: 767N, 2014: 4298N
Launches & Videos