New Gun, couple issues

[SA80Dan]

I think I told you wrong actually, I think those are more like half MOA adjustments/100m not 1 MOA as I was thinking. So if that's the case and given you're 2 inches off at 50 yards, you might need to come over 7,8 or so - which would bring you closer back to center no?

[jackblack73]

If you're off 2 inches at 50, that's more like 8 clicks of adjustment if the sights are 1/2 inch per click.

[ejewels]

Yeah. So weird to me though. Why would he bore sight it and then when shot at 50 on a rest (so not a lot of shooter error and my groups were pretty tight) would it be off like that? Maybe the kid messed up the bore sighting. IDK.

[jackblack73]

I thought people only used bore sighting to get on paper. I never considered it an accurate way to zero sights.

[26 Inf]

Yeah. But assuming I need to come 2" over on target at 50 yards, would the sight adjustment be close to normal? Trying to decide if I take in the gun or not. Also, the 50 yard range is about an hour away. I do have a 25 yard indoor range close to me. Would zeroing at 25 still show if anything is off, or should I stick with a 50 yard zero?

You need to read a couple of the stickied threads on zeroing and trajectories - they are at the top of the AR General Discussion homepage.

Personally, from reading your initial post, I would go with a 100 yard zero, which can be accomplished on a 25yard range - see linked target thread below.

https://www.m4carbine.net/showthread...100-Meter-Zero

https://www.m4carbine.net/showthread...mp-300M-Zeroes

You may not be able to download the pdf any longer, but you can still do the offset required at 25M - essentially you zero it 1.5 inches low at 25 yards, which would be .75 low at 50 and zeroed at 100 yards.

Since the 25 yard range is closer, and I imagine you will shoot more there, I'd zero at that range.

You posted: even though the guy bore sighted it... it was shooting left an inch or two at 50 yards afterwards.

Assuming you have a 1/2 moa sight (Troy's are 1/2 moa) That means that you would move the strike of the bullet 1/2 for each click at 100 yards, or 1/4 inch at 50 yards.

So if you were 1 inch left you would need to move 4 clicks right; 1.5 inches move 6 right; 2 inches move 8 right. I would make those adjustments if you were shooting a group at 50 yards.

That would give you a tentative zero to start with regardless of which range you are using.

If you are wanting to use the 25 yard range, each click of windage would move the bullet 1/8 inch on your target with a 1/2 moa sight.

Hope this helps.

[ScottsBad]

Thanks. I actually put the pic of the rear sight up just now too. So people purposely don't load mags fully because they won't feed that way? Why would it feed if the bolt was already back, but if the bolt wasn't back when the mag was inserted and I charged it myself it then didn't feed?

I live in a ten round state too (CA). The 10 round mags are very unforgiving. If you try to load a full 10 rounder on a closed bolt it is likely that the mag will not seat properly because 10 round mags don't have much play.

If you want a reliable (and legal) situation you must load the mag on an open bolt.

If you must insert on a closed bolt you'll have to strip a round off to insure a reliable seating of the mag.

The reason that the 10 round magazines have insufficient play is because of the ridiculous laws. If a cop wants to arrest you they can, if they can find ANY way to add a eleventh round to the magazine. It matters not if the mag is made for 10 rounds or if it will even work with an eleventh jammed in. Some cops will call it illegal if they can force in another round and it is somehow retained by the magazine.

Because of this ridiculousness, Magpul and other manufacturers look out for their customers by making it impossible to insert an 11th round. However, this makes it nearly impossible to seat a full 10 rounds on a closed bolt.

When you insert on a closed bolt, the bottom of the bolt inserts itself into the magazine which pushes the rounds and the follower deeper into the magazine. If there is insufficient room for the rounds and follower to move down, the magazine may not seat properly.

The best idea is to learn to ALWAYS insert a magazine on an open bolt.

[gaijin]

I thought people only used bore sighting to get on paper. I never considered it an accurate way to zero sights.

It’s not.

[MegademiC]

Yeah. So weird to me though. Why would he bore sight it and then when shot at 50 on a rest (so not a lot of shooter error and my groups were pretty tight) would it be off like that? Maybe the kid messed up the bore sighting. IDK.

Boresighting is useless. It just gets you in paper at 50/100yds.

You can do the same visually.

Never trust anything other than rounds on target to result in rounds on target.

[26 Inf]

Its weird... on the troy sights I'm not sure what constitutes "clicks". It seems I have to click it maybe 8 times before its even noticeable. If I zeroed at 25 though, I could at least still see if things are off correct? Like if its an inch to the left at 25, it would be maybe another inch off to the left at 50? Because Maths. lol.

Each 'click' counts as a click. At 50 yards four clicks would equal an inch on the target with your sight. You have a Troy sight which moves the rear sight blade 1/2 moa per click. That means each click of the rear sight moves the bullet strike 1/2 inch at 100 yards, 1/4 inch at 50 yards and 1/8 inch at 25 yards.

So 8 clicks would move your 1/2 moa sight 4 inches at 100 yards, 2 inches at 50 yards, and 1 inch at 25 yards.

Yes, if it is one inch left at 25, it would be 2 inches at 50 and 4 inches at 100.

Also, you want to move the rear sight in the direction you want to move the strike of the bullet. The TRoys I have are marked with an arrow and the letter 'R' which means turn it in the direction of the arrow to move the strike of the bullet to the right.

You might want to do some searches, both here and on google for sight adjustment and trajectory.

[ejewels]

Thanks for all the help everyone. So I didn't get to the range, but I took it into the gun shop today. He moved the rail slightly and told me to go shoot it before he had to do some other adjustments and then bring the target to him. But now the rail is kinked over a little so not sure I'd want it permanently like that. I'm thinking of just taking it to Troy themselves as its a complete upper built by them. They are local to me so I figure why not. Straight to the source. I'm thinking they could either replace it or take a hard look at it and know what needs to be adjusted... saving me rounds and all.