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harbl_the_cat
10-12-2012, 11:13 AM
A friend of mine who recently got his PAL with minimal shooting experience had me writing a long winded e-mail to him about how he should go about zeroing a prospective rifle for hunting/varmint control.

I've only hunted once before, but shoot quite a bit and have worked retail at a gun store. Most of the information I've given him are either from what I've heard from others or learnt myself.

If I've lead him down the wrong path, can someone with more experience let me know?

He was interested in getting one of these guys:

http://ca.wholesalesports.com/storefront/firearms/bolt-action-rifles/model-11fxp3-111fxp3/prod203078.html

This was my e-mail to him:

That .270 would be a pretty safe bet as well.

Just be warned, some folks are critical of the packaged combo rifles, complaining the optics are low quality. That said, some people's expectations are pretty ridiculous. A deer hunting rifle doesn't have to be super precise to do the job. It's not like if you're unable to hit a penny out to 100 yards that you'd be incapable of hitting a deer.

On zeroing a scope:

My recommendation regardless of what you pick up, would be to just pony up $40 for a day pass (or find someone who has a membership and get in for $20) at THE SHOOTING EDGE (not the Calgary Shooting Centre) and get 3-4 boxes of the ammo you plan to hunt with. Both are good ranges, but TSE has a 50 yard rifle range, CSC does not. 50 yards is the bare minimum you need to zero a rifle, in my opinion. 25 yards is too close to get a reliable zero - since you'd have to make massive adjustments on your scope to get any change on your point of impact and even then, your group size would be so small it's hard to say if it will actually be zero'd out to longer ranges.

Before you zero, make sure you're scope mount is on tight, secured by some threadlock (blue-loctite is recommended) and make sure your scope rings aren't loose. If you're really unsure, talk to Stephan (the gunsmith) - just be warned, being hunting season, most of the gunsmiths in town will have a huge backlog to burn through (I took my .308 to get repaired a few weeks ago and had to wait 2 weeks to get it fixed). Ask the range staff if anyone knows how to set up and zero a rifle as well (some will, some won't).

Do some Google searches and find out the "50 yard zero" for .270, doing a 2 minute google search it sounds like it's 0.5" high to be on target at 200 yards. It's a general guideline and a lot of things can change it (mainly barrel length, but also the ammunition and weather conditions - another plus to shooting indoors, is there's no wind or weather to factor into the equation). That said, usually the zeros from gun to gun of similar calibre don't change TOO much that the zero is worthless.

This zero means, at 50 yards if you set the point of aim of your scope on the centre of a cross pattern target, and fire 3 shots - you should be able to get a group matching the MOA (minute of arc/angle) of your scope's reticle and you'll want it to be 0.5" high of the point your aiming at. I'm assuming it would be 1MOA scope (MOA is the size, in inches, at 100 yards) - so a 1/2 inch grouping at 50 yards should be attainable. I believe the formula is:

Group size in inches = scope reticle MOA * (sighting distance (yards) / 100 (yards)).

Your scope will have elevation (vertical) and windage (horizontal) adjustment dials. For the kind of hunting I think you'll be doing, all you need to do is get a solid zero in advance and provided your scope mount is solid and you're scope is not broken, you should not need to change the adjustments while in the field. Only extreme range/precision shooters/snipers worry about field adjustments of their scopes to adjust for conditions - you and I as Joe-blow hunter/sport shooter just need to know approximate hold-over.

The same formula for MOA applies with the adjustment dials only:

Shift in point of impact in inches = adjustment dial MOA per click * number of clicks * (sighting distance (yards) / 100 (yards)).

They usually are listed on the dials themselves in 1/4 or 1/2 MOA per click increments - meaning at 50 yards, on a 1/4 MOA scope dial, 1 click of the dial will equal a 1/8th inch shift in point of impact in the direction of the click. Either your scope may not be perfectly setup vertically/horizontally, or you may shoot with a bit of a cant, so it's not inconceivable that shifting your horizontal zero may cause your vertical zero to shift (or vice versa). While you should try to minimize this, it's not a show stopper, provided you similarly compensate the opposing shifts on the corresponding dial. All that matters is you being able to make a 3-5 shot grouping consistently, and adjusting the scope so it's on the zero.

When zeroing as well, use the most stable platform you can - ideally using a rest and secure table (TSE's rifle range setup is perfect for this). Don't bother shooting unsupported (either standing or sitting) unless you've done a zero from a rest. Nobody I know (who's not Swiss) can shoot unsupported as well as they can supported - so after you've done a zero on your rifle supported, don't be surprised if you're group size doubles or quadruples unsupported. It doesn't matter - at 50 yards, unsupported with a 1MOA scope, a 2-4" grouping unsupported will still probably get a deer in the freezer up to 200 yards.

Especially for hunting, once you have a zero, you're going to want to practice taking snap shots - that is, lowering the rifle (so your sights are not on target), bringing it up, acquiring your sight picture, and shooting as fast as you can. If you're chasing, deer are fast little buggers and you may only have a few seconds to get a shot off. Even if you're in a stand or blind, posting, a deer crossing an open path may only present itself for a few seconds. IMO, while it's important to be able to make a 3 shot, 1" group, when you take 2-3 minutes to do it it's probably as important if not more so to be able to able to get a 3 shot, 4" group in under 20 seconds (although that's just my personal opinion).

Also, especially shooting bolt action sporting/hunting rifles - try to keep the amount of shooting to a minimum. Unlike semi-auto or military style rifles, there generally is no gas system or recoil buffer system. This means all the superheated gas from the cartridge goes towards propelling the bullet down range. This causes 4 things that could adversely impact your shooting: a sore shoulder (and twitchy muscles), a warmed up bore and barrel, a dirty bore and barrel, and wear and tear on your optic and mount.

The first 2 are easily mitigated - shoot a grouping, take a break.
The third is a bit of a hassle - run a patch of oil and bore brush through your barrel to clean it up
The last one could be a day/hunt killer - since you could potentially cause your scope mount to wobble loose or break your scope. If this happens, you have to fix your optical system, which would basically completely destroy your zero.

Once a scope is removed, even if it's advertised as being able to "return to zero" you have to assume it's zero is lost - it may hit close to your original zero - but especially for entry level optics/guns, I'd just assume the zero is lost until I can confirm it. That said, if you notice on a hunt that the scope is wobbling - provided you're able to re-secure your it, set up a target at 50 yards, confirm where the scope is hitting and just carry on (some may disagree with me on that one).

As a personal standard - with an entry level hunting rifle, I personally would commit no more than 50 rounds to zero, practice, AND hunt with before re-zeroing it.

This process is repeatable with any caliber, and scope.

Some shops you should check out:
Alberta Tactical Rifle Supply
Calgary Shooting Centre (even being robbed they have some really good stuff)
The Shooting Edge
Canadian Tire Macleod
Wholesale Sports

Sorry if that's a bit of a novel - shooting is my passion and I love to share info about it :)

JustBen
10-12-2012, 11:36 AM
Most cheap scopes don't have MOA written on the dials. The basic ones read 1 click = 1/4" @ 100 yards. Oh, and don't turn the dials the wrong way!

I always try to get on paper at 25 yards, followed by fine tuning at 100 yards. If you are off the paper at 25 yards, cut the distance in half.

RobSmith
10-12-2012, 01:42 PM
Gotta be a little careful with the 25yds on paper followed by 100yds zero trick though. I remember messing around trying to sight in a 30-06 and even though it was dead center at 25 there were no impacts at 100. I had blown thru I don't know how many rounds trying to figure out what the problem was then an old-timer approached, looked at it, and said "if you're dead on at 25 you're going to be a couple of yards over at 100" Sure enough he was right, I dialed the scope almost a full turn down and was finally able to finish the zero.


Most cheap scopes don't have MOA written on the dials. The basic ones read 1 click = 1/4" @ 100 yards. Oh, and don't turn the dials the wrong way!

I always try to get on paper at 25 yards, followed by fine tuning at 100 yards. If you are off the paper at 25 yards, cut the distance in half.