How flat is flat?!?

[staudacher]

One thing to also remember when watching shooting videos.

Guns that appear to shoot flat in a video shot at 30fps won't look all that flat at 300 or 600fps.

Max's gun probably jumps around more than it looks like in the above video. It isn't how flat it shoots but how predictable the gun returns to the intended POA. IMO

A guy told me once he could hold a Glock completely flat when he shot. He even showed me a video to prove it. So I made him a video at 300fps. You should have seen the look on his face when I showed him the video.

Edited June 4, 2014 by staudacher

[staudacher]

Here is an example of a 9mm Major open gun that does not return to POA like moverfive's gun does. The actual muzzle flip up isn't much more than the muzzle flip of Brad's gun however you notice when the gun comes down it dips well below intended POA.

Now the big question how much is the gun and how much is the shooter? How would the recoil of the 9mm major gun shown here differ if Brad was shooting it? Or viva-versa how would the recoil of Brad's gun changed with someone else shooting it?

Edited June 4, 2014 by staudacher

[kneelingatlas]

Too heavy a recoil spring???

[staudacher]

Too heavy a recoil spring???

Maybe. Maybe not. I can replicate the same problem by just gripping too hard.

[moverfive]

Too heavy a recoil spring???

Yes, the recoil spring was WAY too heavy. I had been all over Tom to lower his spring weight but resisted. After seeing this video as compared to my gun - he changed springs and the performance improvement was very dramatic.

[moverfive]

Little Max's gun is going to flip more than many guns because he is using 7625.....it just doesn't work the comp as well as some powders.

He has learned the timing of that gun due to the many hundreds of thousands of rounds he has shot. For those of us without that luxury, using better powders and such will shorten that learning curve a bit. :-)

Think about it - go back 20 years when the standard open load was WW540 and a 135gr bullet. We didn't have hybrids then and the comps certainly weren't the best designs either. So we used a fast powder, heavy bullet, and not the best compensation system.......we had LOTS more flip and movement back then. Yet, we still could shoot VERY fast and accurate......because we knew the timing of the guns.

And yes, it is the indian and not the arrow.......if that was the case, the top limited guys wouldn't be beating a lot of good open shooters. :-)

[earthshine402]

Too heavy a recoil spring???

Maybe. Maybe not. I can replicate the same problem by just gripping too hard.

Not sure that gripping too hard could cause the muzzle dip. If anything, I would think that gripping very hard would reduce motion in all directions. Are you sure you don't mean the post-ignition push?

[staudacher]

Too heavy a recoil spring???

Maybe. Maybe not. I can replicate the same problem by just gripping too hard.

Not sure that gripping too hard could cause the muzzle dip. If anything, I would think that gripping very hard would reduce motion in all directions. Are you sure you don't mean the post-ignition push?

Call it what ever you want to call it. I have experimented with it and had a couple other people also try it and every time the harder they gripped the gun the more pronounced the muzzle dip became.

Now don't get me wrong the gun setup can also be at fault. And as Brad mentioned in the case of Tom's 9mm Major gun that was at least part if not all of the problem. Basically it comes down to a combo that works for you.

Edited June 5, 2014 by staudacher

[stevepitt]

Moverfive-

I'm curious about your comment on 7625 powder.
I'm running a Trubore comp with 7625 with 124gr JHP's in Supercomp and have noticed the excessive dot movement. I recently tried VV N105 and am undecided about it. I like the way the dot settles better, but it seems pretty harsh in the hand. What powders do you consider better than 7625? (I know what some choices are for 3SC, but would like to hear what you consider better specific to dot movement).

Thanks,

Steve Pitt

[moverfive]

Here is the problem that so many people have when determining what is the best load for them.......they worry too much about how the gun feels. The feel of the gun should not really enter the equation.

When you are shooting a stage, do you really hear or feel the gun? No, you don't. The ONLY thing that should matter is the dot movement and its predictability.

I make those statements about 7625 because I shot it for a few years. Then I was introduced to N105 and gave it a try. To say that my dot movement with N105 was less than half what I saw with 7625 is an understatement. When I went to Vhita Vuori's website to look at their burn rate chart (which I consider the absolute best since it shows powders side-by-side as opposed to linear), I then understood why that was the case: 7625 is a fast burning powder.

http://www.lapua.com/upload/downloads/brochures/2014/vihtavuorireloadingguideed12_2014eng.pdf

On page 2 is their burn chart. You can see where it is just slower than N320, faster than AA5. And that is why the dot movement sucks for me - I think it is way too fast.

So looking to the more common powders used in Open, you can read across to find options that work for you.

In my case, AA7 and N105 are my two preferred powders in the Super line. 3N38 would be my next choice.

Vihtavuori Reloading Guide - Edition 12.pdf

Edited June 5, 2014 by moverfive

[Supermoto]

I used 7625 in super, loved it. I found it soft and flat. I tried N105, did nothing for me that 7625 didn't.

I have tried 3n38, 3n37, 4756 also. 7625 was the powder that caused the dot to return to POA best for me

Edited June 5, 2014 by Supermoto

[cnote]

.

[Shadow]

Here is the problem that so many people have when determining what is the best load for them.......they worry too much about how the gun feels. The feel of the gun should not really enter the equation.

This. Let a timer tell you what powder is best for you.

[kneelingatlas]

I loaded some HS6, just to experiment and save my precious SP2 and damn! you can see it flip considerably more in the video (to be fair these loads are closer to 165pf than 170+, so they might flatten out with more powder):

[robot]

I loaded some HS6, just to experiment and save my precious SP2 and damn! you can see it flip considerably more in the video (to be fair these loads are closer to 165pf than 170+, so they might flatten out with more powder):

Looks pretty normal to me.