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My son and I went to Elm Fork this morning. I brought a couple of AR carbines, my AR10, and my M1 Carbine. My son brought along a couple of AR carbines, his M1A, and his .308 bolt rifle. We started on the 50 yard line. I finally got both mine and my wife's carbines properly zeroed at 50 yards and then made sure the irons were dialed in. Then I unlimbered the M1. I love that gun. Surprisingly accurate too, given what it is. With my tired eyes, I was able to put 10 rounds into about a 2.5" circle at 50 yards. That's minute-of-critter for anything you'd care to shoot with a .30 carbine bullet.

Next we moved over to the 100 yard line where I set up with my AR10. I've struggled to get this rifle to shoot since I bought it, but couldn't decide if the problem was me or the gun. It is supposed to be optimized for the 175 grain Matchking and pretty high velocity, but I've shot a number of different handloads through it and had a lot of trouble getting it to group right. I've even seen keyhole impacts before with it. Anyway, today I ran a couple of boxes of Federal 7.62 NATO match with the 175 grain Matchking, and it finally started to do OK. I discovered that I was having a lot of parallax error if I dialed the magnification up all the way at only 100 yards (at full power the scope is 20X). So I dialed the magnification back to 11X and everything started to stabilize nicely. Still not GREAT groups, as it should be shooting .5 MOA, but I was able to pretty consistently shoot 1 MOA, and was able to put 3 rounds into a ragged hole 3 or 4 times. Then I had my son shoot five rounds of the same ammo, and he put 4 rounds into one hole, with a 5th round flyer about .75" out......and that was the first time he's ever fired that rifle.

I'm getting old.

Anyway, it was good to know that I hadn't gotten hoodwinked into buying a lemon. I just need to buckle down and get really used to shooting this rifle. It can shoot. It just needs a good shooter behind the scope. I've got a learning curve, and it's been frustrating because I've never had difficulty wringing good results out of my other rifles.

My son had a ball shooting his Savage and his M1A. All in all it was a good day, and I never get tired of spending time with my son at a range.

The Annoyed Man wrote:All in all it was a good day, and I never get tired of spending time with my son at a range.

This made me smile! Due to some genetic & physical issues that my son has it is likely that we'll never be able to share this experience. But, we do lots of other fun things together. And my girls will get to learn as much about firearms as I can teach them (or pay to have them taught).

Every day at the range is a good day as long as everyone leaves with the same number of holes they came with. Being able to share them with loved ones -- particularly teaching them and learning from them -- can make range days great.

Russ, I can't believe you didn't share WHY you were at the range today!

Today is Take Your Daughter to the Range Day! Some ranges had some special activities going on. I hope some of you were able to share in this day!

Unfortunately, I am in DC where we don't even mention the "g" word, and I left my revolver shaped house key at home even, LOL! 'bout peed myself when they swabbed hands at the Capital building for "gunpowder and explosives residue". Glad I am a frequent handwasher

Tam how many rounds do you have thru the AR10? The two I have were over 200 rds before they settled in and they prefer 168 gr ammo. They even like the PPU ammo in 168 gr.

Sidro wrote:Tam how many rounds do you have thru the AR10? The two I have were over 200 rds before they settled in and they prefer 168 gr ammo. They even like the PPU ammo in 168 gr.

I've put about 200 rounds through it so far, and the previous owner had about 300 rounds through it if I recall correctly. He claimed to have gotten better results than I have so far, but I think he also shot it from a lead sled or something like that. I have the shooter's log from when he owned it and his results were in the .5 to .75" range. The log book had one group of 4.5" at 600 yards listed, which seemed pretty good to me since you never know what is going to happen at longer ranges. A rifle that shoots tiny groups at 100 yards may not shoot at the same MOA at longer ranges.

But you never know if you can duplicate someone else's claims. I was beginning to think that I'd been taken a bit, but today's results went a long way to restoring my faith in the rifle. I don't want to keep buying Federal 7.62 NATO Match. It's pretty expensive stuff. So if I can duplicate the load I'll be pretty happy at the money saved.

Divided Attention wrote:Russ, I can't believe you didn't share WHY you were at the range today!

Today is Take Your Daughter to the Range Day! Some ranges had some special activities going on. I hope some of you were able to share in this day!

Unfortunately, I am in DC where we don't even mention the "g" word, and I left my revolver shaped house key at home even, LOL! 'bout peed myself when they swabbed hands at the Capital building for "gunpowder and explosives residue". Glad I am a frequent handwasher

I didn't know there was such a thing as Take Your Daughter to the Range Day! I did take her last Saturday, though.
Any day at the range is a good day.
TAM, if I could shoot with my tired old eyes and get 2.5" with my M1 Carbine I'd be ecstatic! What brand scope is it with the high power parallax problem? Warranty???

Sorry, DA, about not mentioning it in this thread. I did share it in another thread.

puma guy wrote:What brand scope is it with the high power parallax problem? Warranty???

It's not really a "problem" with the scope, per se, and it isn't really a warranty issue. The scope is a SWFA 5-20x50HD, and it is a superb optic. The glass is very bright and clear, with no distortion around the edges at high magnification. I had a chance to compare it to a couple of very high end Leopolds and an IOR scope before buying, and it compared very favorably to those scopes. It's just that parallax can be an issue in any rifle scope, and the higher the magnification, the more pronounced the error is if you don't have your eye in exactly the right spot relative to the eyepiece. This can be true for any brand, including the very top end scopes. It makes the image seem to move around and it can be hard to center in the eyepiece. (This is why a holographic sight like an EOTech is so superior for CQB—it doesn't matter how your eye position moves around, the reticle stays on the target.) So when I dial the scope down to 10X or so, it is easier to avoid parallax error, and things smooth out. OTH, people routinely use this scope on rifles out to 1,000 yards, and at that distance, the 20X setting isn't nearly so jumpy. It's a $1,500 scope, and it has a really good tactical milling reticle with 11 illumination settings, and the stadia lines on the reticle are perfectly matched to the .1 mil increments on the adjustment knobs. I buy another one in a heartbeat if I had another $1500 burning a hole in my pocket.

This is the scope: http://swfa.com/SWFA-SS-5-20x50-Tactica ... 51642.aspx



The scope is really nice and. If I ever sell the AR10, that scope is going on my Remington 700.

Myself, Fenster, and another forum buddy all hit the range today and blew through a TON of ammo. I'll post vids later of the action shooting.

The Annoyed Man wrote:The scope is a SWFA 5-20x50HD, and it is a superb optic. . . . It's just that parallax can be an issue in any rifle scope, . . . It's a $1,500 scope,

Don't high end scopes usually have parallax adjustment?

Jumping Frog wrote:

The Annoyed Man wrote:The scope is a SWFA 5-20x50HD, and it is a superb optic. . . .  It's just that parallax can be an issue in any rifle scope, . . . It's a $1,500 scope,

Don't high end scopes usually have parallax adjustment?

Parallax is often misunderstood. Here is an explanation on Optics Talk, a forum owned by SWFA, written by one of the SWFA owners: http://www.opticstalk.com/what-exactly- ... c5026.html

Parallax 
Parallax is essentially an optical illusion.  Parallax presents itself as the apparent movement of the reticle, in relation to the target, when your eye moves off center of the sight picture (exit pupil) or in more extreme cases it appears as an out of focus image. It indicates that the scope is either out of focus or more specifically the image of the target is not occurring on the same focal plane as the reticle. Maximum parallax occurs when your eye is at the very edge of the sight picture (exit pupil). Even when parallax is adjusted for a designated distance, there is an inadvertent error at other distances.  Most brands of scopes that do not have a parallax adjustment are pre-set at the factory to be parallax free at or around 100 yards; rim fire and shotgun scopes are set at or around 50 yards.  Most scopes of 11x or more have a parallax adjustment because parallax worsens at higher magnifications.  Generally speaking parallax adjustment is not required for hunting situations and is primarily a feature used and desired by target shooters.  A 4x hunting scope focused for 150 yards has a maximum error of only 8/10ths of an inch at 500 yards.  At short distances, the parallax effect does not affect accuracy. Using the same 4x scope at 100 yards, the maximum error is less than 2/10ths of an inch. It is also good to remember that, as long you are sighting straight through the middle of the scope, or close to it, parallax will have virtually no effect on accuracy in a hunting situation.

This is another way to think of it that maybe you can relate to.  You know when you are sitting in the passenger seat of a vehicle its hard to look at the speedometer and tell how fast you are going because your eye....the needle....and the mph number are not all three lined up.  So to you it looks like your going 35 when really you are going 55.  But the person behind the steering wheel has his eye..the needle and the mph all lined up straight in the same focal plane and gets a true reading.  Its not exactly the same thang but close enough for government work.

What most people think of as "parallax adjustment" would actually be better thought of as a focus knob—sometimes located on the back of the scope, sometimes located in a knob on the left side of the scope opposite the windage adjustment knob—which permits the user to fine tune the focus to the magnification to the distance of the target. On this particular scope, it is a side-focus knob. On my 4.5-14x50 VXIII, it is on the back of the scope, at the exit pupil. This SWFA scope has focus adjustments from zero out to 1500 yards, beyond which it is marked an "infinity symbol" (can't type it on my iPad). Either way, as the above explanation points out, it isn't entirely a matter of focus. Fine tuning the focus helps, but it doesn't cure the phenomenon. The cure is in training the operator to correctly position his/her eye relative to the scope's exit pupil (and this is why holographic sights for close up are so wonderful.....they remove parallax error from the problem of locating the target in the reticle).

In my case, the parallax issue I am experiencing on my scope is because I am having difficulty finding the "sweet spot" behind the eye piece where the image is perfectly centered in the scope, and just the crosshairs are perfectly centered over the image, but only at the higher magnification. In case you want to know what 20X looks like, it makes something that is 1,000 yards away look like it is only 50 yards away to the naked eye. This parallax effect is maginified at highest magnification, and minimized at lowest magnification. Thus, the problem is me, not the scope. And, this type of problem is common to high magnification scopes, regardless of brand. That is not to say that everyone will experience it at high magnification, but some do, and I'm one of them. I regard it as a matter of training.