This is bound to get long... so thanks for hearing me out.
SO... It all started when my oldest decided he wanted to start hunting. Any excuse is a good excuse to get a new gun! I decided on a set of consecutive serial numbered Ruger American Compacts in .308 for him and his little brother when he got old enough. Figured since I reload I could download to appropriate recoil and he'll never outgrow it. Well we had great success with finding a load that worked and he tagged his first deer on our second day out. Couldn't have been prouder. I'm hoping that one day he'll be able to claim to have only harvested game with cartridges he made.
Fast forward to a few weeks ago, Cabela's is running a deal on the new RA Predator in 308 and I just so happen to have enough Cabela's bucks to get it free and clear. (which is also how I got the boys') Now I've got essentially the same gun that's just enough different that there is no mistaking "Dads".
I've long been a fan of the .308 and am looking forward to trying a number of different rounds including the reduced recoil rounds that I made for jr. but I start thinking about the nightmare of having to re-sight-in every time I want to use a different round.
It dawned on me that (in a perfect world) I might be able to develop rounds that would have the same ballistic path. So I popped open a Hornady reloading manual, fired up the internets, a reloading program or two and started chugging numbers.
SO: (all examples are for illustration purposes only) Starting with the assumption that the largest load brings the most challenges, I tried to identify what speeds the other loads would need to be at to match this path. THEN, accepting that I live in MN and would rarely get a shot beyond 150yd I also identified a zero that maintained a flat +/-1" trajectory for each load.
I would however like to use this occasionally at longer "moderate" ranges out to 300yd primarily for hunting purposes. For that reason, I listed holdovers, and the yardages that the energy dropped below 1000ftlb as well as the velocity falling below 1900fps. (Obviously subjective numbers, but lets just humor me for now...) Just for fun, I included some relative recoil numbers.
It looks like "in theory" (and I know each barrel/load combination is going to like whatever speed it likes...) I could get a 130Gr Reduced recoil, a 150Gr, a 165Gr and a 180Gr to all shoot to the same point of aim, zero'ed at 140yd and staying within a 2" range (+1": 85yd, -1": 160yd).
So the question is: Will it work? Has anyone tried this? If so is there a name for it? I'd love to be able to have recipes for 4-5 particular loads that all work with the same scope setting or at least within a few clicks. Maybe have the turrets set to zero for the 165gr and have a chart for the minor adjustments for the others if I HAD to?
I've tried to attach the chart I worked up. Hopefully that works so that it illustrates a bit better what I'm going for. I figure with three guns in the house it'd be a fun longer term experiment for the boys and I. However, if I'm going to be chasing rabbits down a bunny hole, I'd rather hear it now.
Also, yes I'm aware that my predator has a different contour barrel than the compact, but its the same length and twist, so for now I'm ignoring that fact.
Any thoughts you can share would be MOST helpful.
Supporting info:
*Reduced Recoil (H4895: 41Gr)
**Sub-Sonic (IMR Trail Boss: 10gr)
Muzzle Velocity "Achievability" Verified with Hogdon .308 Pistol Data (15" Barrel)
http://www.hodgdonreloading.com/data/pistol
Short Barrels don't reduce accuracy:
http://www.tacticaloperations.com/SWATbarrel/
SO... It all started when my oldest decided he wanted to start hunting. Any excuse is a good excuse to get a new gun! I decided on a set of consecutive serial numbered Ruger American Compacts in .308 for him and his little brother when he got old enough. Figured since I reload I could download to appropriate recoil and he'll never outgrow it. Well we had great success with finding a load that worked and he tagged his first deer on our second day out. Couldn't have been prouder. I'm hoping that one day he'll be able to claim to have only harvested game with cartridges he made.
Fast forward to a few weeks ago, Cabela's is running a deal on the new RA Predator in 308 and I just so happen to have enough Cabela's bucks to get it free and clear. (which is also how I got the boys') Now I've got essentially the same gun that's just enough different that there is no mistaking "Dads".
I've long been a fan of the .308 and am looking forward to trying a number of different rounds including the reduced recoil rounds that I made for jr. but I start thinking about the nightmare of having to re-sight-in every time I want to use a different round.
It dawned on me that (in a perfect world) I might be able to develop rounds that would have the same ballistic path. So I popped open a Hornady reloading manual, fired up the internets, a reloading program or two and started chugging numbers.
SO: (all examples are for illustration purposes only) Starting with the assumption that the largest load brings the most challenges, I tried to identify what speeds the other loads would need to be at to match this path. THEN, accepting that I live in MN and would rarely get a shot beyond 150yd I also identified a zero that maintained a flat +/-1" trajectory for each load.
I would however like to use this occasionally at longer "moderate" ranges out to 300yd primarily for hunting purposes. For that reason, I listed holdovers, and the yardages that the energy dropped below 1000ftlb as well as the velocity falling below 1900fps. (Obviously subjective numbers, but lets just humor me for now...) Just for fun, I included some relative recoil numbers.
It looks like "in theory" (and I know each barrel/load combination is going to like whatever speed it likes...) I could get a 130Gr Reduced recoil, a 150Gr, a 165Gr and a 180Gr to all shoot to the same point of aim, zero'ed at 140yd and staying within a 2" range (+1": 85yd, -1": 160yd).
So the question is: Will it work? Has anyone tried this? If so is there a name for it? I'd love to be able to have recipes for 4-5 particular loads that all work with the same scope setting or at least within a few clicks. Maybe have the turrets set to zero for the 165gr and have a chart for the minor adjustments for the others if I HAD to?
I've tried to attach the chart I worked up. Hopefully that works so that it illustrates a bit better what I'm going for. I figure with three guns in the house it'd be a fun longer term experiment for the boys and I. However, if I'm going to be chasing rabbits down a bunny hole, I'd rather hear it now.
Also, yes I'm aware that my predator has a different contour barrel than the compact, but its the same length and twist, so for now I'm ignoring that fact.
Any thoughts you can share would be MOST helpful.
Supporting info:
*Reduced Recoil (H4895: 41Gr)
**Sub-Sonic (IMR Trail Boss: 10gr)
Muzzle Velocity "Achievability" Verified with Hogdon .308 Pistol Data (15" Barrel)
http://www.hodgdonreloading.com/data/pistol
Short Barrels don't reduce accuracy:
http://www.tacticaloperations.com/SWATbarrel/
