Long range vernier advice.

I'm using the expander plug and a card wad now, I just thought that it might be easier with a dedicated die. It occurred to me that I could use the expander die from my .458 too, since I'm not using it. A dummy bullet and the seating die would work too. So far all I've used are milk carton wads, what I have coming are .030 vegetable wads.


Youl eventually want to experiment with polyethylene wads, felt, wax paper, newspaper and god know what else wads as you'l likely be using a grease cookie in the future. Keep an eye out at garage sales or flee markets for a 9/16 arc punch you can drill out.
 
At long last my sight arrived this morning. :)

Next order of business is to level the sight to match barrel level which near as I can tell is correct. Any thoughts or tips on that?

I clamp the rifle in a rest and use a good level on the staff to ensure that when the spirit level shows it's level, the staff is also perpendicular.

If you plan on shooting in competition, once you have the sight perfectly perpendicular you will probably want to shim it so that it's a little to the left to compensate for the spin drift of the bullet. Right hand twist will move the bullet to the right, increasing with distance. Lots of people think it only matters at long range, but even at 500m ( ram distance ), the correction is better than one minute. A thin shim of between 0.006" to 0.008" under the right edge of the sight will get you pretty close to where you want to be for a .45 cal with a 1:18 twist.

Here is a clip from the Shiloh forum by the late Dan Theodore regarding setting up your sight....

Here's the equation to determine bullet drift that's a function of bullet spin.

3.4 X t^2 = Bullet Drift in Inches

So, the equation is 3.4 times the time-of-flight squared to calculate bullet drift. In our case the typical time-of-flight is about 3 seconds from the 1,000-yd line. So, that would be 3.4 x 9 = 30.6 inches of bullet drift over 1,000 yards or about 3 MOA (half the width of the target.)

My LR rifles are set up so that the calm zero is the mechanical zero at 800, 900 and 1,000 yards. Bullet drift from spin, also know as "spin drift", is nonlinear. That is, its rate-of-drift (like acceleration) increases with range which can be seen in the time-squared variable in the equation.

I've developed a relatively easy way to set the rifle's sights up so this can be accomplished. First, the rifle is locked into a vice or placed in a cleaning rack, so it will not move easily, with the front-sight bubble centered-up. With the eyecup removed from the rear staff, a magnetic level is attached to the side of the staff that doesn't have the elevation knob so the level will be parallel to the staff. The bubble should be about 6" to 8" above the staff pivot point. One wants to shim the staff-base to the left (shim(s) under the right side of the base when standing behind the rifle) so that the bubble just touches the right side of the line in the bubble when standing behind the rifle. Once this is accomplished; shoot at 100 yards off-the-sticks so that bullet impact is about 1" to 1.5" to the left of the X. Move the front sight to accomplish the appropriate bullet impact. This procedure is for right-hand-twist barrels. Reverse the process for left-hand twist barrels.

If you follow the above procedure, you should be pretty close to matching your mechanical zero with the calm-wind zero at LR distances. My rifles are set up so that at each LR yard-line, if it is calm, the sight can be put on mechanical zero and the bullet impact will be in the middle of the target horizontally. Shooting in boils is a good way to work on fine-tuning the front sight.

If one has their sights so setup, it is a distinct competitive advantage, especially when the wind is switching badly. During a major wind-direction change, one can go to their mechanical zero and estimate just one wind direction and magnitude instead of estimating what the value of the wind was (direction and magnitude) and then adding that estimate to the estimate of the new wind value (direction and magnitude.) That is 4 estimations and twice the error as compared to just going to one's mechanical zero and making just the estimate for the new wind direction and magnitude.


Chris.
 
When I set mine up I went to great lengths to ensure that the rear staff was as close to perpendicular to the front sight dovetail cut out as I could manage. I used the dovetail "floor" because the octagon faces turned out to have a slight crown to them.

Then I found that my shots drifted to the right as I was increasing the range. I figured I'd messed up my alignment. Then some time back a helpful sort like gunlaker mentioned spin drift and the light went on over my head.

Lot's of little things to learn......

I've also been out shooting more this past couple of months. I think Santa is going to be bringing me an MVA rear sight for Christmas this year. I'm about fed up with the sloppy feel of the Pedersoli rear sight.

They DO make nice guns. But the rear Soule style sight just doesn't match their other work. On the other hand they cost a lot less than the MVA or other options.

Or maybe it's time to use my machine shop and make some for myself that address all the issues I've found.
 
I've been giving it a bit of a workout in the last couple weeks and fell like I'm making progress. The sight stem has a bit of a left tilt to it, but as near as I can tell the mechanical windage zero holds true from 100 to 650 yards. That's as far as I've taken it so far.

There's plenty of work to do on loads, and I've need a differnt bullet lube, but the 1/2 mile Buffalo goal does seem to be within reach. 174 on my vernier for 650, with 81 for 100.
 
this thread has deflated my balloon, scored a Pedersoli sight and came looking for info and everyone is poopooing it
will manage to make it work good'nuff for me
the rear screw through the tang is kind of janky but I think I have it secure
 
It wouldn't be the best for competition if that's where your plan is, but you will be able to make it work. If before you were just using a regular peep or especially open sights, you'll have a very big improvement.

Chris.
 
It wouldn't be the best for competition if that's where your plan is
and why is that?

have read more about it and find the negative comments were likely base-less?
Pedersoli has several levels or grades of sights, base econo to highest grade comp. ready
this one is middle, a mid-range Silhouette model
comments of shaking loose certainly isn't an oem problem
 
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The main problems with some of the sights out there are too much slack in the soule drum, and marks that are imprecise or hard to read. The MVA sights have the best engraving of marks on the staff and soule drum of any that I've used ( MVA, Pedersoli, Shaver deluxe & AMT ( Winchester/Browning BPCR ). They also don't seem to develop so much backlash/slack in the soule drum with extended use.

A lot of this stuff won't matter much if shooting in anything other than a match. In a match with time limits, you just don't need to have to deal with those problems. But if you are going to the range with the intention of shooting some gongs out to long ranges, the Pedersoli sight will do fine.

Chris.
 
good day at teh range with the new sight installed
surprised at how easy it was to set up at first, just eyeballing center and height for 100m to start, got lucky i guess with 5 shots to hit the 2" bull
not enough loads on hand for real precision, so just getting some dope for future
+10 for 200
+16 for 300
+15 for 400
Last one for the day was a hail mary maybe at 500, a single shot +15 .....but no dust signature.....
then the 'ding' came back! Unbelievable!
hit the wrong target, was right ~16" but elev. was super good enough, I'll take it!
Still can't get the stupid smile off my face šŸ˜

schitazzedluck I know but til next time it is a win, needed one in life these days
signing off quick before someone bursts my bubble (y)
 
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