PRS Talk Sand fill question

[Slate264]

Hey all,
looking for advise regarding reticle hop while dri firing on a sand filled medium game changer.
I have been using a medium game changer with poly beads for a while now and just recently started experimenting with sand. The sand fill seems more stable but I noticed something interesting. While dry fire practicing with both bags side by side I noticed that the reticle consistently hops after the firing pin drops when Iam using sand bag (around .1, sometimes .2) and not when Iam using poly beads bag. It even does it if I don’t put any weight on the rifle and just look through the scope. I also tried using snap caps which helped alittle but the hop is still there. I Also removed some fill from the bag to see maybe it was too stiff with same results.
Let me know what you think. Thanks

 

[Mormegil87]

1) Make sure your NPA is on point. If it's not, work on that.

2) Try settling/rocking the bag into the sand bag a little and see if that helps.

 

[Slate264]

1) Make sure your NPA is on point. If it's not, work on that.

2) Try settling/rocking the bag into the sand bag a little and see if that helps.

Rocked the rifle into the bag and even tried complete free recoil, so npa wasnt an issue. Iam thinking it happens as a result of firing pin dropping and beads absorb the movement while sand being harder doesn’t? That’s the only thing I can think of

 

[mbeavers1]

What trigger you running?

 

[OREGUN]

Repeat after me, this quote from our lord and savior, the greatest pop singer of all time:

“it’s me, hi, I’m the problem, it’s me”

the heavy sand isn’t the problem, your technique and interface with the rifle is.

Try rocking the muzzle up to the target so the bag squishes into the corner between the stock and the mag. My opinion of game changers is that they almost always come over filled and too stiff. Try taking some more sand out. Work on your engagement with the rifle, hold a little tighter, REALLY CONCENTRATE on excellent follow through. A lot of people will shoot their second shot off a bag better than their first as the first recoil really settles the bag into the sand. You can practice until this goes away. Set the gun onto the bag, push the gun into the bag and drive the muzzle up onto the target, concentrate and follow through. A lot of people pat the bag and wiggle the gun around, etc. All this does is waste time. Practice until you don’t do this. Be really mindful of what your left hand is doing…is it imparting a force onto the rifle? How about your shoulder? Your firing hand? Your cheek? Try a lower cheek height/less cheek pressure. Which way does the reticle jump up or left/right? One is often related to your center of gravity, the other to a misalignment of your hips and shoulders.

Yes, Frank likes to set his gun on a tripod and touch nothing but the trigger and show that he gets an impact….but that’s not the same as watching for 1 or 2 tenths of reticle movement. Yes, NPA is a part of the answer. You can set the gun down such that the reticle is on target but then you have to reach up and interact with it. That’s going to require you interface with the gun in a very closely studied and extremely well executed way. And that takes practice and refinement of gear and technique.

 

[Niles Coyote]

We are on parallel paths... It can be done and as out lined above in @OREGUN tips. I still see it at times with my trigger press and while listening to a recent pobcast with Austin Bushman, I believe on "miles to matches", he was speaking on the hard stop with TriggerTech and others and stated he didn't have that issue with the Bix'n Andy as it has no stop... I have not had the opportunity to try one and see if that helps but it is on my list.

 

[Slate264]

What trigger you running?

TT Diamond

 

[Slate264]

Repeat after me, this quote from our lord and savior, the greatest pop singer of all time:

“it’s me, hi, I’m the problem, it’s me”

the heavy sand isn’t the problem, your technique and interface with the rifle is.

Try rocking the muzzle up to the target so the bag squishes into the corner between the stock and the mag. My opinion of game changers is that they almost always come over filled and too stiff. Try taking some more sand out. Work on your engagement with the rifle, hold a little tighter, REALLY CONCENTRATE on excellent follow through. A lot of people will shoot their second shot off a bag better than their first as the first recoil really settles the bag into the sand. You can practice until this goes away. Set the gun onto the bag, push the gun into the bag and drive the muzzle up onto the target, concentrate and follow through. A lot of people pat the bag and wiggle the gun around, etc. All this does is waste time. Practice until you don’t do this. Be really mindful of what your left hand is doing…is it imparting a force onto the rifle? How about your shoulder? Your firing hand? Your cheek? Try a lower cheek height/less cheek pressure. Which way does the reticle jump up or left/right? One is often related to your center of gravity, the other to a misalignment of your hips and shoulders.

Yes, Frank likes to set his gun on a tripod and touch nothing but the trigger and show that he gets an impact….but that’s not the same as watching for 1 or 2 tenths of reticle movement. Yes, NPA is a part of the answer. You can set the gun down such that the reticle is on target but then you have to reach up and interact with it. That’s going to require you interface with the gun in a very closely studied and extremely well executed way. And that takes practice and refinement of gear and technique.

Thanks for the outline! I do practice what you described above, I even tried complete free recoiling after settling the rifle in and just pressing the trigger which is set pretty light and observing the reticle move through the scope after the firing pin drops. This is all pertaining to dry firing.
not beginner shooter, have numerous top 3 finishes in regional matches and been working on my fundamentals for few years now. Just found it weird that with sand it hops it and with beads it doesn’t. Someone mentioned TT triggers with hard stop, have to check that out.

 

[OREGUN]

Thanks for the outline! I do practice what you described above, I even tried complete free recoiling after settling the rifle in and just pressing the trigger which is set pretty light and observing the reticle move through the scope after the firing pin drops. This is all pertaining to dry firing.
Just to put in perspective, not beginner shooter, have numerous top 3 finishes in regional matches and been working on my fundamentals for few years now. Just found it weird that with sand it hops it and with beads it doesn’t. Someone mentioned TT triggers with hard stop, have to check that out.

I’ve been meaning to try the bix. I have one of their models on a BR gun with a pull weight down around an ounce. It’s cool. Orgain likes the lack of a back wall too, at least the last time I talked to him. I don’t have a poly fill bag to compare to. Grab a different bag, a fortune cookie or something, at the next match and see if it is unique to your game changer maybe? When I was really trying to shoot small kraft groups, I was doing a ton of dry fire and could feel when the reticle was going to move as the trigger broke. The factors were all very subtle body mechanics. It’s not essential on a four tenth wide target so I stopped devoting so much time to it…focusing more on “gross fundamentals” and efficiency now. Maybe see if consciously staying off the back of the trigger makes a difference.

 

[Slate264]

I’ve been meaning to try the bix. I have one of their models on a BR gun with a pull weight down around an ounce. It’s cool. Orgain likes the lack of a back wall too, at least the last time I talked to him. I don’t have a poly fill bag to compare to. Grab a different bag, a fortune cookie or something, at the next match and see if it is unique to your game changer maybe? When I was really trying to shoot small kraft groups, I was doing a ton of dry fire and could feel when the reticle was going to move as the trigger broke. The factors were all very subtle body mechanics. It’s not essential on a four tenth wide target so I stopped devoting so much time to it…focusing more on “gross fundamentals” and efficiency now. Maybe see if consciously staying off the back of the trigger makes a difference.

The hop that Iam experiencing is a mechanical one, it’s almost like a pop when the firing pin drops and not a move based on reticle movement or body position. Iam a big fan of TT and will experiment further. Just interesting that it’s not happening with poly beads bag.I Compared both medium game changers with sand and beads side by side.

 

[mbeavers1]

I’ve been meaning to try the bix. I have one of their models on a BR gun with a pull weight down around an ounce. It’s cool. Orgain likes the lack of a back wall too, at least the last time I talked to him. I don’t have a poly fill bag to compare to. Grab a different bag, a fortune cookie or something, at the next match and see if it is unique to your game changer maybe? When I was really trying to shoot small kraft groups, I was doing a ton of dry fire and could feel when the reticle was going to move as the trigger broke. The factors were all very subtle body mechanics. It’s not essential on a four tenth wide target so I stopped devoting so much time to it…focusing more on “gross fundamentals” and efficiency now. Maybe see if consciously staying off the back of the trigger makes a difference.

This is exactly why I was asking what trigger it was. I started with TT diamonds but could never ever get the reticle to not move. It always moved when I pinned the trigger to watch the shot. I changed to a Bix and it disappeared. The Bix has a touch of overtravel that allows you to follow through the shot without affecting the rifle. I believe the TT 'hard stop' was the culprit for me.

 

[M8541Reaper]

Repeat after me, this quote from our lord and savior, the greatest pop singer of all time:

“it’s me, hi, I’m the problem, it’s me”

Facts..

That plays on repeat after every match for the first hour on the drive home

 

[drglock]

I actually run both triggers, a TT Diamond on my Impact and a B&A on my RimX. I notice what you’re seeing with my TT if I pull on the trigger hard and never see it on the B&A. A lot of it can be what was mentioned above but it also can be from hitting the wall on the TT since it doesn’t have any over travel.

 

[Slate264]

I actually run both triggers, a TT Diamond on my Impact and a B&A on my RimX. I notice what you’re seeing with my TT if I pull on the trigger hard and never see it on the B&A. A lot of it can be what was mentioned above but it also can be from hitting the wall on the TT since it doesn’t have any over travel.

I run the same setup, impact+TT. But the question remains how come the bag with poly beads doesn’t have the hop while sand bag does. This experiment was done while dri firing. Do poly beads absorb that slight movement that a falling firing pin creates better than sand Not sure…

 

[drglock]

I run the same setup, impact+TT. But the question remains how come the bag with poly beads doesn’t have the hop while sand bag does. This experiment was done while dri firing. Do poly beads absorb that slight movement that a falling firing pin creates better than sand Not sure…

What stock/chassis or you running

 

[Slate264]

What stock/chassis or you running

Mpa matrix pro

 

[Baron23]

Eh, I run TT Diamonds and don't have any sort of hop from the trigger and/or its wall.

Er...maybe don't ham hand your trigger?

 

[drglock]

Mpa matrix pro

I’d say try taking a little more sand out and try it and it could be your form. Like said above , maybe too much cheek pressure or your grip. I know I went from you a Cole Tac trap bag with light fill to back to using Shemedium and pint size both with heavy sand and when I get movement like you I know it’s me.

 

[DeathBeforeDismount]

Someone once showed me how to propperly fill a gamechanger (Hes on here). You want to almost be able to pinch your fingers in the middle. Work the bag, wax it and get it nice and broken in. When you put the bag (tits up, which is the correct way) on a pipe or thin barrier, it will naturally make a flat surface for your gun to rest on.

GC all come with way more sand than they need.

 

[Precision Underground]

The reticle twitch is because the poly beads give and the sand does not. So when the firing pin drops, that force is transferred into the scope vs into the bag. Free recoiling will actually make it twitch more. I’ve seen exactly what you’re taking about and I’m 99.9% sure it’s the reticle springs twitching. It’s def not the whole rifle twitching. So it shouldn’t hurt you on target. But, it is a good lesson on connecting the rifle to your body. When you connect the rifle to your body, make it an extension of your body, it will absorb the impact from the firing pin and the reticle won’t move. Sadly there are very few people who actually shoot this way because balancing on a bag with a brake is easier than learning to drive the rifle.

 

[OREGUN]

If it’s easy, take about 1/4 of the sand out and try it. I think a heavy sand bag will sometimes, depending on how it is set on the prop, get really rigid, especially if overfilled, or wet, and can end up losing that vibration damping characteristic we like. It causes a bounce under firing spring/pin motion. It looks very mechanical…not like a wobble. It’s a rigid looking hop. With all due respect to our esteemed colleague above, I’m not convinced it’s in the scope…my $5000 scope’s reticle sure as fuck better not wiggle under vibration. I think it’s the vibration moving through the rigid system...action, barrel, stock, bag. My early foray in benchrest shooting showed me the great lengths group-shooters will go to to have as little motion in the system when the firing pin is falling as possible. If the bolt body moves when the firing spring tension comes off the sear, the rifle won’t shoot the smallest groups...essentially. Light springs, short pin throw, short lock time, perfectly timed triggers, free recoil, etc…none of which we do for PRS. We have to make up for it by holding on to our rifles and perfecting our interface with the gun.

For example, for some reason I see a lot of this reticle wiggle/hop on trigger press if I throw a tater tot bag over my tripod apex but it goes away if I use a puppy bag. Something about the way the bigger bag drapes over the top instead of “sitting” more on top makes the bag get kinda stiff and act like a teeter-totter. Not only is it harder to slow the wobble but the reticle is also more likely to hop. The tater tot is definitely better on a full size barricade section though. By the way, this is all with an impact/TT setup at about 6 oz of trigger pull.

Also, no one will judge your bag choice, especially if you are winning so use poly if it works better for you. Congrats on taking home some regional points. Now for that AG CUP.

 

[Slate264]

The reticle twitch is because the poly beads give and the sand does not. So when the firing pin drops, that force is transferred into the scope vs into the bag. Free recoiling will actually make it twitch more. I’ve seen exactly what you’re taking about and I’m 99.9% sure it’s the reticle springs twitching. It’s def not the whole rifle twitching. So it shouldn’t hurt you on target. But, it is a good lesson on connecting the rifle to your body. When you connect the rifle to your body, make it an extension of your body, it will absorb the impact from the firing pin and the reticle won’t move. Sadly there are very few people who actually shoot this way because balancing on a bag with a brake is easier than learning to drive the rifle.

Great explanation! Thank you.
I had a feeling it was a difference with the fill and how it absorbs the vibrations of the firing pin dropping. There was also less hop if I used a spent case with spent primer Vs dri firing on empty. The spent primer most likely absorbed some of the energy of the firing pin and it didn’t transfer into the scope

 

[Slate264]

If it’s easy, take about 1/4 of the sand out and try it. I think a heavy sand bag will sometimes, depending on how it is set on the prop, get really rigid, especially if overfilled, or wet, and can end up losing that vibration damping characteristic we like. It causes a bounce under firing spring/pin motion. It looks very mechanical…not like a wobble. It’s a rigid looking hop. With all due respect to our esteemed colleague above, I’m not convinced it’s in the scope…my $5000 scope’s reticle sure as fuck better not wiggle under vibration. I think it’s the vibration moving through the rigid system...action, barrel, stock, bag. My early foray in benchrest shooting showed me the great lengths group-shooters will go to to have as little motion in the system when the firing pin is falling as possible. If the bolt body moves when the firing spring tension comes off the sear, the rifle won’t shoot the smallest groups...essentially. Light springs, short pin throw, short lock time, perfectly timed triggers, free recoil, etc…none of which we do for PRS. We have to make up for it by holding on to our rifles and perfecting our interface with the gun.

For example, for some reason I see a lot of this reticle wiggle/hop on trigger press if I throw a tater tot bag over my tripod apex but it goes away if I use a puppy bag. Something about the way the bigger bag drapes over the top instead of “sitting” more on top makes the bag get kinda stiff and act like a teeter-totter. Not only is it harder to slow the wobble but the reticle is also more likely to hop. The tater tot is definitely better on a full size barricade section though. By the way, this is all with an impact/TT setup at about 6 oz of trigger pull.

Also, no one will judge your bag choice, especially if you are winning so use poly if it works better for you. Congrats on taking home some regional points. Now for that AG CUP.

I don’t think he meant the reticle wiggles, don’t most of them etched into the glass. Most likely what he meant was the crosshairs hop because the sand is harder and it doesn’t give like the beads do which translates into vibration in the scope.

I tried removing about 1/4 of sand like you said and still get the hop.
I used poly for few years and I like the ease of of use and maneuverability but when I tried the sand fill recently it was about 10-15% more stable which was really cool until I started to dri fire with it and noticed the hop

 

[mikeg1005]

I tried removing about 1/4 of sand like you said and still get the hop.

Does it return back to where you were aiming or hops and stay there?

 

[Mormegil87]

I don’t think he meant the reticle wiggles, don’t most of them etched into the glass. Most likely what he meant was the crosshairs hop because the sand is harder and it doesn’t give like the beads do which translates into vibration in the scope.

I tried removing about 1/4 of sand like you said and still get the hop.
I used poly for few years and I like the ease of of use and maneuverability but when I tried the sand fill recently it was about 10-15% more stable which was really cool until I started to dri fire with it and noticed the hop

Stability > recoil management. Every time. All the time. It's hard to make a good correction if you can't say with reasonable certainty where the shot was broken.

Also, IF, you find yourself watching the reticle through recoil, just stop. Watch the plate and back drop, watching the reticle is pointless until it's time to measure your POI vs POA.

 

[Slate264]

Stability > recoil management. Every time. All the time. It's hard to make a good correction if you can't say with reasonable certainty where the shot was broken.

Also, IF, you find yourself watching the reticle through recoil, just stop. Watch the plate and back drop, watching the reticle is pointless until it's time to measure your POI vs POA.

This conversation is regarding dri firing

 

[Slate264]

Does it return back to where you were aiming or hops and stay there?

hops and stays

 

[Mormegil87]

This conversation is regarding dri firing

I know. However what you watch and do during dry fire translates directly to live fire.

If you find yourself focusing on what the reticle is doing during dry fire, you will in all likelihood do the same in live fire. Same for wobble, if you find yourself breaking shots that were wobbly in dry fire in order to minimize reticle movement when the pin drops. You will, in all, likelihood do the same in live fire.

 

[Slate264]

I know. However what you watch and do during dry fire translates directly to live fire.

If you find yourself focusing on what the reticle is doing during dry fire, you will in all likelihood do the same in live fire. Same for wobble, if you find yourself breaking shots that were wobbly in dry fire in order to minimize reticle movement when the pin drops. You will, in all, likelihood do the same in live fire.

You are absolutely correct. Reticle during shot, target during recoil and after. But that’s not what the question was. I was just curious why I was getting a hop with sand and not with poly bag during dry fire with everything else being equal

 

[Mormegil87]

You are absolutely correct. Reticle during shot, target during recoil and after. But that’s not what the question was. I was just curious why I was getting a hop with sand and not with poly bag during dry fire with everything else being equal

I guess my long winded reply could have been summed up a little better. Pretty much; "don't worry about it".

If your NPA is good, your stability is good, your press is good and your stable, that little hop is pretty low on the "things to be concerned about".

If you want to try a different trigger, go for it.

I agonized over this for a couple of years, spending tons of money on bags and chassis and God knows what else. Then I realized, it's just going to do what it's going to do.

 

[mikeg1005]

hops and stays

Then you're inducing the movement into it while pulling the trigger. I've noticed if I'm at NPA and it still moves its usually from input either through my cheek or through my trigger hand. Very subtle but its there.

 

[Slate264]

Then you're inducing the movement into it while pulling the trigger. I've noticed if I'm at NPA and it still moves its usually from input either through my cheek or through my trigger hand. Very subtle but its there.

This is during dry fire. Doesn’t happen with poly beads bag only sand. Also happens when completely free recoiling. It’s more of a mechanical hop after firing pin drops

 

[mikeg1005]

This is during dry fire. Doesn’t happen with poly beads bag only sand. Also happens when completely free recoiling. It’s more of a mechanical hop after firing pin drops

I'm assuming it absorbs more of the vibration than the sand bag. I know when I'm dry firing off my sandbag I get the hop as well but it returns exactly to here the reticle originated from if I execute everything correctly... if it hops and stays there then I'm causing it to shift during the trigger pull.

 

[Slate264]

I guess my long winded reply could have been summed up a little better. Pretty much; "don't worry about it".

If your NPA is good, your stability is good, your press is good and your stable, that little hop is pretty low on the "things to be concerned about".

If you want to try a different trigger, go for it.

I agonized over this for a couple of years, spending tons of money on bags and chassis and God knows what else. Then I realized, it's just going to do what it's going to do.

Can’t argue with any of your points.
It was just an interesting phenomenon that I noticed and haven’t seen anyone discussing it so just wanted to run it by knowledgeable people. That’s the Beaty of this forums.

 

[Slate264]

I'm assuming it absorbs more of the vibration than the sand bag. I know when I'm dry firing off my sandbag I get the hop as well but it returns exactly to here the reticle originated from if I execute everything correctly... if it hops and stays there then I'm causing it to shift during the trigger pull.

Yeah that’s what other people were saying on here. Sand doesn’t give and transfers vibrations into the scope when firing pin drops where poly beads give alittle and vibrations are not transferred. I gotta check again if returns, I just assumed it doesn’t