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realredman
04-16-2013, 09:06 PM
I have a SWFA SS 20X42 fixed power .10 mil click and mil/dot scope. It has 13.5mils up and 13.5mils down elevation. My zero for 100 yds is 15.26 up from dead zero down with 0 MOA mount and med rings. My question is will I have enough down to re zero at 100 yds if a 15 MOA mount is used.

Also with my new found 27 (there abouts) mils up. How far will I be able to go out? 168 hpbt@2700fps?

BoilerUP
04-16-2013, 09:38 PM
A mil is 3.6 MOA...so yeah, you're plenty good with a 15MOA base.

If your current zero is 15.3 off full down adjustment, a 15MOA base will make that roughly 11.2 off full down, about 15.8mil of up elevation.

With a 168 SMK @ 2700, that'll get you past at least 1100yd. For that range though, you'd probably be better served with the 155 Palma or a 175/185.

GSXR
05-03-2013, 12:21 AM
Go to jbm calcs, its free. If you already know the speed of your load that helps ALOT. Plug In all the values, bullet type, air temp, humidity, elevation, your zero what ever It may be etc. etc. and It will give you a pretty good idea. Will produce bullet drop and wind drift In mils or moa, which mils Is what you want since your scopes reticle and adjustments use It. The 175 matchkings could very well be a better bullet for your gun at distance, the 155s are for palma shooters that use barrel lenghts around 30 inches which I dought you have. The 155s where designed for a very specific class of shooting and are not always a good choice for standard barrels lengths out to the extented distances you plan on shooting, without the extremely longer barrels the 155s may not have the velocity to accurately make it out to those distances without going sub sonic. Another suggestion if you havnt already is learn the mildot system for ranging targets, formula Is easy and it works. The heavier bullets retain energy and velocity needed at longer ranges, will out of say a 24 inch barrel the 155s will have more speed entially than the heavier ones but out past 6 or 7 hundred yards they taper off quickly In windy conditions, lots of wind drift unless there pushed extremly fast, velocities you simply cant achieve with standard length barrels. Doesnt do alot of good to have a bullet shoot out to 1000 yards that holds a 3 foot group because of the elements like the wind. Play with the numbers, you might be surprized at how much your load will drop from a 100 yard zero out to 1000 yards. Id guess in the neighbor hood of 35 feet. Round 11 mils of drop so you shouldnt have any problem doping your scope to get there. 1 mil at 100 is 3.6= .360 for one click with 1/10mil turrets. 1 mill at 200=7.2 1 click at 200 =.72 1 mil at 1000 =36inches 1 click = 3.6 inches. Things sometimes look good on paper but real world conditions will surprize you. You get the idea.