Spin drift: Why do people say it doesn't matter?
- Thread starter Roddy
- Start date
arcticcathonda
CGN frequent flyer
- Location
- Southern Alberta
I know AB includes aerodynamic jump within the solution, perhaps shooter does the same thing when it identifies a cross wind is applied.
I think the "Jury" is still out on the topic. A few are somewhat opposite Brian on the topic. One side(Gus Ruiz and Jim Boatright) sees it more as a short term phase just after muzzle blast and for about 10 yards afterwards. More of a "launch disturbance" than a long term continuous effect.
That tends to support early "jump" and not much to see after a 100 yard target. It appears Brian Litz saw otherwise. Both have good research and points however the topic seems to be in flux as research becomes better.
I don't think ATRAG has it either although newer software updates may have captured it.
Another point is that wind is such a factor that some of the smaller variables are simply ignored.I don't really know anyone that uses software on the firing spot for solutions. Plus not every team has a computer, whether it be Mil/LE. You simply have to prep beforehand and adjust if you have to.
If one seriously shoots, one needs all the pre planning help you can get whether you shoot competively or Mil/ LE. That includes info on ranges, angles, fencing, etc. Then you can use cheat sheets, memorized wind constants, barrier penetration angles or whatever at the location if that suits your needs.
First thing I'd recommend for LE guys is to get a scaled Plot Plan of their city from the City Planner/Engineer. That will be worth its weight in diamonds when the bat phone rings.
If you shoot competively maybe get your dope on your rifle with addition of whatever you need and can put into the zero(spin, etc if that suits your needs)and then work up wind bookends like Komby posted and work up you wind constants for you load. Then when you leave the line you'll be confident on that stage, in that environment, AND if it changes from your bookends, you have your constants to fall back on or from adjustments from the first round.
I'm always impressed by guys that compete. They shoot in a hurricane at long range under time limits. Much harder than shooting from 56 yards.
Probably right.... Slow learner I suppose.
I've only shot out a half dozen barrels playing F Class over the last 15 years or so years.
Somehow or another despite my inexperience, I've miraculously managed to rack up a "few" nice awards.
But hey, I'll keep at it and I'll figure this ballistic thing out eventually.
And the safety stuff which he himself mentioned having to consciously worry about.
There were competitors there that have won major F-Class matches, national PR and SR matches, and even the Queens Medal. It was new to them too.
There were competitors there that have won major F-Class matches, national PR and SR matches, and even the Queens Medal. It was new to them too.
This is all very interesting discussion and as Rugbydave refefenced, PRS is a very different game (not saying the best or anything just different). All shooting sports are great and each one will bring something to the table. I personally think PRS guys have to thank F-Class/BR guys for somethings (load development techniques/loading skills/etc.).
There are no sighters in a PRS match and no walking it in on a target. Depending on the COF you may get a chance to spot your misses and then correct but you might not either. Personally, my matches are often unlimited round count so maybe you can correct in time but that comes at the cost of maybe not making it to the next target. I know when I read Komboyatch's Meaford COF it was different - his had a larger priority on first round hits and had limited round counts.
Even if you hit steel on your first round if it is far enough away it can behard to tell if it is a dead centre hit or maybe a far right/left hit and you can do the same thing again and have a miss.
Edited to add: I am sure a PRS shooter could try and go do some F-Class and have his behind handed to him just as well as someone going the other way.
There are no sighters in a PRS match and no walking it in on a target. Depending on the COF you may get a chance to spot your misses and then correct but you might not either. Personally, my matches are often unlimited round count so maybe you can correct in time but that comes at the cost of maybe not making it to the next target. I know when I read Komboyatch's Meaford COF it was different - his had a larger priority on first round hits and had limited round counts.
Even if you hit steel on your first round if it is far enough away it can behard to tell if it is a dead centre hit or maybe a far right/left hit and you can do the same thing again and have a miss.
Edited to add: I am sure a PRS shooter could try and go do some F-Class and have his behind handed to him just as well as someone going the other way.
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
Bingo... Been in F class long enough to have a solid grounding on the tech side. PRS appeals to me because it puts ME into the mix... and me is now alot older, and slower then the last time I was in this gendre.
Each game brings its own basket of needs and opportunities and I look forward to relearning how to shoot and move again.... heavy emphasis on the MOVE part
WRT to aerodymanic jump, spin drift and other corrections related to the BULLET, I can tell you that this body of info is changing and going to change as more experience is gained in transonic and subsonic flight. If I were trying to write a program, I would just stick in an average and know it will rarely be perfect for many popular options out there.
But on the upside, the amount this correction is in steady state conditions is relatively small, that it is unlikely to be the main reason for a miss. When shooters can hold sub 1/2 MOA fire from weird and wonderful positions and targets way out there start getting alot smaller, math error here isn't going to amount to much.
I will be worrying on establishing a stable position first, finding the target, then wind.. if I have any brain power left, I will keep that for remembering such important things like how to close my bolt and/or remove my safety.
1/4 MOA this way or that at 1000yds will truly be lost in the noise.... of the heart pounding in my ears... or the changing wind direction - directional or relative or some combo of both... yeah do the math here and see where energies would be better placed.
Worry less.. shoot more... score BETTER.
Jerry
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
If you want to share your experience, great to hear how things went for you.
I compete in FTR out to 1000yds and the rule of thumb is 1/4 min left for each 300/350yds... if a combo is going to spin drift more then this, I would love to know.. so I can avoid it
Worst I am going to be off is 1/4 min (more then likely less then that) at 1000yds using this adjustment (minus wind of course)... I ain't missing a target because of that.
But I am always happy to learn... and maybe there is a very simple solution to help you out????
Bullet, twist rate and muzzle velocity if you want to share... and at what distance did you start to feel that POI was not quite what you were expecting?
Jerry
