Very accurate load but too slow...

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Very accurate load but too slow...

Post by Super Dave on 4/18/2017, 9:07 pm

Hi,

My goal was finding loads that were very accurate with mild recoil.  They were beautiful on the bench.  But I found them too slow offhand.  It seems that my flyers are magnified with poor follow through compared to the faster loads.

Here's an example of a slow but accurate load.
Precision Delta 148 HBWC, 2.9 HP38, S&W model 14-5    Avg vel. 677fps

When I bump the speed up my off hand accuracy is much more consistent.
Precision Delta 148 HBWC, 3.0 Bullseye, S&W S&W model 14-5, 6"   Avg vel 807fps

It seems like a faster bullet will mask some errors in concentration.  Do any of you have a certain velocity range that you look for?

Thanks,
Dave

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Re: Very accurate load but too slow...

Post by Magload on 4/18/2017, 9:09 pm

45 ACP  680 to 710.  Don
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Re: Very accurate load but too slow...

Post by Jon Eulette on 4/18/2017, 9:19 pm

What distance (fliers)? Light loads for 25 and slightly warmer for 50. I can shoot down to 3.4 gr BE with 200 gr lswc and get away with it at 50, but I have to concentrate a little harder. I think slower velocities magnify our flaws in our fundamentals. i just finished shooting my 3.4 load in a new pistol I just finished and it was shooting equal to Federal Match at 25. So I would question your trigger squeeze over the ammo velocity. No offense Smile
Jon
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Re: Very accurate load but too slow...

Post by Magload on 4/18/2017, 9:26 pm

What Jon said.  You answered it with this sentence, They were beautiful on the bench.  That bullet doesn't know if it is being held or shot out a a gun on a rest.  I really don't think a little velocity is going to correct a bad trigger pull.  If it did I would be shooting +P loads.  Don
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Re: Very accurate load but too slow...

Post by Super Dave on 4/18/2017, 9:40 pm

Right.  Yea, it's all me.  I mostly shoot at 25 yards.  I don't compete...just a guy that likes to shoot and I don't mind taking short cuts if there are any!  

Sounds like you guys are all about the fundamentals and that's admirable. 

Thanks,
Dave

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Re: Very accurate load but too slow...

Post by Magload on 4/18/2017, 9:55 pm

Dave I know what I am supposed to be doing just can't seam to do it anymore.  All this was easier 50 years ago.  Don't seam to remember my hand shaking back then and a swear a good trigger pull is harder to come by.  I to just do it for fun as I don't think I have enough shooting years in me to shoot High Master.  I do like the technical stuff and enjoy reloading and testing loads.  Benchrest pistol is probably my favorite way to shoot.  My girlfriend asked if I didn't get tired of doing this gun stuff everyday.  i told her when I could clean a target benchrest at 1000yds with my 45 I would quit and stay home and do honey dos.  Don
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Re: Very accurate load but too slow...

Post by Wobbley on 4/18/2017, 10:27 pm

Dave: I don't think it's your follow through so much as it magnifies other inconsistencies.  Grip pressure, trigger release, wobble etc.  with a slow velocity the bullet has that much more time in the gun.  I bet most of the fliers are high?

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Re: Very accurate load but too slow...

Post by Magload on 4/18/2017, 10:31 pm

Wobbley wrote:Dave: I don't think it's your follow through so much as it magnifies other inconsistencies.  Grip pressure, trigger release, wobble etc.  with a slow velocity the bullet has that much more time in the gun.  I bet most of the fliers are high?
I wish one of the math majors on this sight would tell us how much more time a bullet spends in a 5" barrel when going 100 fps slower.  Don
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Re: Very accurate load but too slow...

Post by Super Dave on 4/18/2017, 10:38 pm

Thanks guys.


 I bet most of the fliers are high?


That's right.  A lot of times they are high.  But, they can also be low too.  What is the cause of the high fliers?

Thanks,
Dave

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Re: Very accurate load but too slow...

Post by Dr.Don on 4/18/2017, 10:41 pm

Factory 148 wadcutter ammo (Remington Targetmaster comes to mind) chronos 700fps.  That's almost NO difference from 677.
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Re: Very accurate load but too slow...

Post by Super Dave on 4/18/2017, 11:08 pm

Factory 148 wadcutter ammo (Remington Targetmaster comes to mind) chronos 700fps.  That's almost NO difference from 677.

Yes, but I was talking about a change from 677 to 807 fps.

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Re: Very accurate load but too slow...

Post by dronning on 4/18/2017, 11:19 pm

Magload wrote:
Wobbley wrote:Dave: I don't think it's your follow through so much as it magnifies other inconsistencies.  Grip pressure, trigger release, wobble etc.  with a slow velocity the bullet has that much more time in the gun.  I bet most of the fliers are high?
I wish one of the math majors on this sight would tell us how much more time a bullet spends in a 5" barrel when going 100 fps slower.  Don

4.167 msec
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Re: Very accurate load but too slow...

Post by Jon Eulette on 4/18/2017, 11:26 pm

On a slightly different note......a 5" 1911 is more forgiving to shoot than a 6"!
Jon
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Re: Very accurate load but too slow...

Post by Magload on 4/18/2017, 11:38 pm

Jon Eulette wrote:On a slightly different note......a 5" 1911 is more forgiving to shoot than a 6"!
Jon
That makes sense that is why I shoot my 4.1" 9mm RO with a dot so well.  With the dot you do not need the long sight radius.  Don
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Re: Very accurate load but too slow...

Post by james r chapman on 4/19/2017, 6:28 am

HP38 being ww231, I think your to light anyway.
I've always seen 3.1 @ 710 fps to be the sweet spot for the 148.

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Re: Very accurate load but too slow...

Post by Chris Miceli on 4/19/2017, 7:41 am

Jon Eulette wrote:On a slightly different note......a 5" 1911 is more forgiving to shoot than a 6"!
Jon
^^
I think it makes the good shots and iffy shots worse =[  Very punishing to shoot.
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Re: Very accurate load but too slow...

Post by bdas on 4/19/2017, 12:49 pm

dronning wrote:
Magload wrote:
Wobbley wrote:Dave: I don't think it's your follow through so much as it magnifies other inconsistencies.  Grip pressure, trigger release, wobble etc.  with a slow velocity the bullet has that much more time in the gun.  I bet most of the fliers are high?
I wish one of the math majors on this sight would tell us how much more time a bullet spends in a 5" barrel when going 100 fps slower.  Don

4.167 msec

Well, that number (4.167 milliseconds) is assuming that it's going 100fps slower during the entire time it's travelling down the barrel, which is not an accurate representation of the situation.  4.167ms is the time it would take something going 100 feet-per-second to travel 5 inches.  But in this case, both bullets start out at rest (0fps) and accelerate to their muzzle velocity in 5 inches.  So a bullet with a muzzle velocity of 750fps will not spend 4.167ms longer in the barrel than a bullet with a muzzle velocity of 850fps.  To get the correct number, you'd need the acceleration curve for each bullet (because it's almost certainly not linear acceleration), but the time-in-barrel difference is probably close to 2 milliseconds (0.002 seconds)

To give you some scale, human visual response latency time is generally agreed to be around 250 milliseconds (0.25 seconds).  (Meaning you're always living a quarter second in the past when you rely on visual stimuli.  That's quick enough to do amazing things like catch a ball unexpectedly sent your way or dodge a punch, but slow enough to explain why trying to snatch a shot once you perceive that the sights are aligned to the center of the bull does not work.)

I've never seen a measurement of the time it takes a pistol to go from "trigger is far enough back to start the firing sequence" to "initial bullet movement", but I would not be at all surprised if that number varied by more than 2ms from pistol to pistol, even among pistols of the same basic mechanism (i.e. among 1911s).  Meaning that, if you're worried that the lag time between pulling the trigger and the bullet exiting the barrel is enabling your wobble or lack of good follow-through to take your point-of-aim off center, you might be better served by cleaning and installing fresh springs in your pistol than adding 100fps to the round (or better yet, do both!).

There are so many more variables that affect accuracy than bullet velocity, it's almost impossible to have an opinion about whether or not the OP's flyers are due to velocity or due to something else (powder, crimp, seating depth, seating straightness, brass, primer, temperature, humidity, gun cleanliness, diet, and on and on).  There's no way around the fact that, if the rounds consistently group fine when bench rested ("consistently" implies more than 2 tries), but not offhand from the same gun on the same day, the problem is the shooter, not the round; you need to behave more like a bench.  And, as Magload pointed out, if additional bullet velocity was all that was needed to successfully mask wobble or trigger pull problems, people would be shooting +P loads (at least in slow fire).  Which you could try, if you wanted to really test the theory.

Dave

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Re: Very accurate load but too slow...

Post by Magload on 4/19/2017, 1:50 pm

There would also be another benefit to shooting +P ammo, and that would be for the shooters that thinks their gun kicks to much.  After a few +Ps a light load will seam like nothing.  If you want a kick I will let you shoot my Shield 45 with +p ammo.  BTW it is a fine shooting carry gun.  I have owned one in 9mm. 40 S&W and the 45 is by far my favorite and best shooting.  Being a short barrel the bullet isn't in the barrel as long either.  LOL  Don
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Re: Very accurate load but too slow...

Post by LenV on 4/19/2017, 2:01 pm

I agree and disagree with what Dave (bdas) just said. All of the physics and math agree. But, there is a thing called recoil dynamics or Newtons law, choose the term you prefer. A longer barrel or a slower load lets the recoil effect the point of impact more than a hotter load or shorter barrel would. The best example of this I have ever seen is using a Ruger Super Blackhawk with 44 special or 44 mag ammo. At 50 yds using the same sight setting you would expect the 44 mag to impact higher on the target then the 44 special. All of the ballistics say the bullet should shoot flatter and impact higher. But, unless your Superman the 44 special will print higher every time. I am talking shooting offhand and not using some kind of machine rest. I used the Ruger as an example because of the rounded grip. Try it sometime and see if I am right. The recoil starts lifting the barrel instantly upon ignition. The longer barrel or slower bullet lets it lift just a tiny bit more. Grip shape, barrel length, velocity, arm strength all effect your POI. That is why we can't use our bench rest zeroes.
  All of the above is why I use 110gr XTP hot loads for my 14-6 for the long line. I am not home so I can't give you the load info. But, it's hot Smile

Len
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Re: Very accurate load but too slow...

Post by LenV on 4/19/2017, 2:18 pm

Not home, but I do have a horrible picture on my flip phone. Apparently I use 4.2gr of Bullseye powder with the 110 gr bullet.

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Re: Very accurate load but too slow...

Post by Magload on 4/19/2017, 2:25 pm

Len you are right and example is when shooting a pistol with fixed sights that is shooting low you can go to a heaver bullet that is slower and the POI will raise.  By playing with your loads you can get your POA and POI petty close with out having to take a file to the fixed sights.  Now when you have to meet a a min PF it is a little harder.  I dislike fixed sights with the dot on the front blade as they normally come from the factory set for a combat hold where the dot is the POI.  I have seen so many post on the forum I was on before with a new gun owner saying their new gun shoots low.  Someone then puts the picture with the 6 o'clock hold, top of the blade hold, and the combat hold and the problem is fixed.  Don
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Re: Very accurate load but too slow...

Post by james r chapman on 4/19/2017, 2:59 pm

I have a minds picture of Lens saboted 110 gr .32 in his 14_2 over 6.4 gr power pistol.


Then I awoke, trembling....
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Re: Very accurate load but too slow...

Post by robert84010 on 4/19/2017, 5:05 pm

well I'm far, FAR from a math major but you don't need to be one to do kinematics. based on constant acceleration: 

V(2)^2=v(1)^2 + 2A*S
V(2)=V(1) + A*T



I get a additional time delta of .15mS when going from 800fps to 700fps. Since we are only talking about .127 meters here the time delta is small, but I agree with Jon, it makes a difference on target if you are moving while the bullet is traveling. please show the formula you are using to correct me if i'm wrong, so I can learn something.


Last edited by robert84010 on 4/20/2017, 9:39 am; edited 1 time in total

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Re: Very accurate load but too slow...

Post by LenV on 4/19/2017, 10:32 pm

james r chapman wrote:I have a minds picture of Lens saboted 110 gr .32 in his 14_2 over 6.4 gr power pistol.


Then I awoke, trembling....
James:  Not to add to your nightmares but. Alliant says you can load that bullet in a 38 special +p with 6.5 gr of Power Pistol. Snappy at 1200 fps but felt recoil is less then my 9mm. Not a legal DR load but fun for CF and Reeves matches. Put a dot on that 14-5 or my 14-6 and shoot little groups. Very Happy And it's .357

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Re: Very accurate load but too slow...

Post by bdas on 4/20/2017, 11:47 am

LenV wrote:I agree and disagree with what Dave (bdas) just said. All of the physics and math agree. But, there is a thing called recoil dynamics or Newtons law, choose the term you prefer. A longer barrel or a slower load lets the recoil effect the point of impact more than a hotter load or shorter barrel would. The best example of this I have ever seen is using a Ruger Super Blackhawk with 44 special or 44 mag ammo. At 50 yds using the same sight setting you would expect the 44 mag to impact higher on the target then the 44 special. All of the ballistics say the bullet should shoot flatter and impact higher. But, unless your Superman the 44 special will print higher every time. I am talking shooting offhand and not using some kind of machine rest. I used the Ruger as an example because of the rounded grip. Try it sometime and see if I am right. The recoil starts lifting the barrel instantly upon ignition. The longer barrel or slower bullet lets it lift just a tiny bit more. Grip shape, barrel length, velocity, arm strength all effect your POI. That is why we can't use our bench rest zeroes.
  All of the above is why I use 110gr XTP hot loads for my 14-6 for the long line. I am not home so I can't give you the load info. But, it's hot Smile

Len
Len, you're talking about the barrel moving at recoil speed during that extra time in the barrel, and probably way more than 130fps difference between those loads.  Out of curiosity, how much difference is there in the point-of-impact?  A few inches?  I don't think even the worst flinch is moving the gun at recoil speed.

Regardless of whether it's 2ms (my bad calculation) or 0.15ms (the right answer), the extra time in barrel is exceedingly small, and not nearly enough time to cause fliers.  Here are two ways to think about it...

1) If you have a MantisX, or have seen traces from a MantisX, the yellow line represents 250ms.  So, the "extra" movement from your wobble or flinch while that slower load is in the barrel is around 1/1666th of that yellow line.  Even for a really bad flinch, 1/1666th of that yellow line is an almost imperceptible difference in POA.

2) Look at super slow-motion footage of a person firing a pistol.  From the first sign of ignition until the bullet leaves the barrel, there is no perceptible movement of the hand or pistol frame.  It just happens way too fast.  

Here's the most educational one I've seen (https://vimeo.com/48571597), as it shows the pistol firing at various frame rates from 30 frames per second, up to 10,000 frames per second.  The best segment for this discussion is at 9:20 of the video.  At 10,000 frames per second (each frame is 0.1 milliseconds), it takes 5 frames (0.5ms) to go from nothing happening to the bullet being a couple inches out of the barrel.  In that span, the hand and pistol frame appear to be immobile.  At lower frame rates, you can see that this shooter often anticipates the recoil and breaks his wrist down and thus aims the pistol down before it goes off, and you can see the results of that down range, as he hits the bottom of the water bottles, clays, and plates.  That is perceptible movement creating fliers, but it's happening before ignition, not while the bullet is traveling down the barrel.  

Yes, that is a faster bullet in a shorter barrel, but even if it took 5 more frames for your slower round to exit your 6" barrel, the amount of movement of the pistol due to wobble/flinch while the bullet is in the barrel would still be negligible.  And the difference between a slower load and a faster load would be far less than that, maybe 1 or 2 frames (i.e. strongly supporting that the calculated value of 0.15ms is correct).

I'm not saying it makes zero difference; there is movement and the time in barrel is not zero (it might turn barely-a-10 into a 9).  And I'm not doubting the experiences of high masters who say that shooting a longer-barreled gun is more difficult (for whatever reason).  I'm doubting the explanation that poor shots are due to slower loads or longer barrels resulting in the bullet spending extra time in the barrel, and thus being more affected by the shooter's wobble/flinch/bad follow-through.  It is simply not enough extra time in the barrel to even begin to explain fliers.


Last edited by bdas on 4/20/2017, 12:08 pm; edited 2 times in total (Reason for editing : minor clarifications)

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