Posted: 10/12/2011 8:14:18 AM EDT
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I know, I know, this has probably been asked many times before on here but I'll try it again. I just recently got in my WOA service upper with the 1/4 x 1/4 sights. I plan on sighting in at 100 yards to get my first initial zero. Now, what I want to get feed back on is the come ups for the 200, 300, and 600 yard ranges from anyone else who has this same set up. From what I've seen and heard, they tend to be right around the same give or take a couple clicks. Please keep in mind I dont have a range available to get these zeros from live fire. The only time i can actually shoot these ranges is during a match, but I have yet to make it to one. There is a match coming up in a few weeks and I would like to get a good starting point for each yard line so I can at least have some hits on paper. I have the Jim Owens data book with the standard come ups, but I would like to get a group average amongst the rest of the shooters.
Also I will be shooting 77gr SMKs (black hills remans) using a 6' oclock hold if that helps any. |
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Everyone uses the same come-ups, it doesn't matter if you are shooting WOA or RRA, half minute or quarter minute adjustments. When you go to the match, you should be able to get your mechanical zero at 200yds. Mark this setting on your rifle and make sure that you keep good records in your log book. The last couple years I have borrowed RRA rifles from the Navy that have 1/2x1/2 sights. They are standard match guns and we are issued 77gr Black Hills Sierra Match King ammo. I usually come up 2.5 to 3 minutes from 200yds to 300 yds, and another 7.5 to 8 minutes from 300 to 600yds. Your come up will change depending on temperature, light conditions, wind, etc. The point of come-ups is to get you on paper so that you can fine tune your sights.
Another thing to pay attention to is the target in your log book. The front cover has the size of the rings in inches. You can see that the x ring is about one minute of diameter at 300 and 600 yds. It also shows the diameter of the other rings. On your score sheet it has dashed lines marked 1/2, 1, 1 1/2. These are meant to help you make those fine adjustments as your shooting conditions change. For example, if you use 7 minutes to come up from 300 to 600 yds (that would be 28 clicks on your 1/4 MOA sight) and you have a group of shots that are in the nine ring/low, you need to come up about 3/4 MOA to get to the X (based on the dashed lines). e.g. one minute at 600 yds is about 6". Dead center to the edge of the x is 3". Dead center to the edge of the nine ring is 9". You will have to move your group 6" which is about 1 minute. The book recommends 3/4 minute, so that is pretty close. Does this help? |
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Using a Rock River upper, and for ammo: 75gr Hornady BTHP, 24.0gr Reloader 15 at 200 & 300; 80gr Hornady AMAX, 24.0gr Reloader 15 at 600. Here are my standard come-ups: From 100 to 200, 2.25 MOA From 200 to 300, 3.25 MOA From 300 to 600, 12.25 MOA Depending on the peculiarities of your range, your ammo, and the light on the day of your match, I'd guess around there would get you in the neighborhood.
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Quoted:
I know, I know, this has probably been asked many times before on here but I'll try it again. I just recently got in my WOA service upper with the 1/4 x 1/4 sights. I plan on sighting in at 100 yards to get my first initial zero. Now, what I want to get feed back on is the come ups for the 200, 300, and 600 yard ranges from anyone else who has this same set up. From what I've seen and heard, they tend to be right around the same give or take a couple clicks. Please keep in mind I dont have a range available to get these zeros from live fire. The only time i can actually shoot these ranges is during a match, but I have yet to make it to one. There is a match coming up in a few weeks and I would like to get a good starting point for each yard line so I can at least have some hits on paper. I have the Jim Owens data book with the standard come ups, but I would like to get a group average amongst the rest of the shooters. Also I will be shooting 77gr SMKs (black hills remans) using a 6' oclock hold if that helps any. Sir, in my humble opinion Mr. Ajroyer has provided a very thorough answer to your question. I would add that in my experience most across the course HP shooters zero their rifles at 200yd. Having said that when I want to shoot a reduced course match at 100yd I have enough remaining downward elevation adjustment to adjust a half minute down. From 200yd to 300yd I adjust up three minutes or twelve clicks for 1/4X1/4 sights. I'll stop at that point because I don't use the 77gr. SMK beyond 300yd and the loads I do use shoot much flatter at 600 so my sight come ups are irrelevant to your question. I will also add that the BC of the 77gr SMK is an indication of how much the bullet slows beyond 300yd and therefore you should keep in mind the BH ammo you are using will require a greater elevation come up to maintain center due to the slower terminal velocity at 600yd. HTH, 7zero1. |
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The answers above should work for you. Just to add, come ups will also vary whether you hold center mass all the way back or 6 o'clock. Just another variable.
I remember rough come ups by: "2 to 2, 3 to 3, 10 to 6" (2moa from 100 to 200, 3moa from 200 to 300, 10moa from 300 to 600) Keith |
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Write your base comeups/windage settings from mechanical zero on a small piece of paper and clear tape it to your buttstock. I had to do this at first and shot my 2 sighters the same exact way without adjusting for elevation, only windage. After the sighters I would figure my elevation setting then tweak my base windage to bracket for conditions and plug away.
Did this for 200/300. Followed pretty much the same procedure for 600 but I made sure I fired both sighters when the mirage was moving in the predominate direction/speed if possible. I found if I shot with the mirage in a boil it really screwed with my elevation settings and I would chase it. ETA: just saw your post was from October. How did you do in the match? |
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Sorry for the delay DKM, its pretty good, I'm no Master, but so far its been the best most reasonable price load I've tried. I'm not in the league to be shooting SMK's. I was shooting 24.1 grains with the 75 HPBT Hornady's which was ok, but the 77 is better. Let me know how you make out. I picked up a 1000 bullets for 147.99 shipped which I thought was a great price. |