Jump to content
SASS Wire Forum
Sign in to follow this  
Kirk James

Sight lift between heavy vs light bullets of the same power factor

Recommended Posts

If two different loads produce the same power factor, is there a difference in the amount of sight lift?  96 grain vs 125 grain  Is there a difference in the noise hitting a target?

Share this post


Link to post
Share on other sites

the heavy slow bullet will hit higher,,, a slower bullet takes longer to leave the barrel thus hitting higher as the barrel has begun to lift from the recoil.   not sure about report from the target

Share this post


Link to post
Share on other sites
1 hour ago, Kirk James said:

If two different loads produce the same power factor, is there a difference in the amount of sight lift?  96 grain vs 125 grain  Is there a difference in the noise hitting a target?

Ha!! You're an instigator!! :lol: 

According to these guys ... (assuming you are associating sight lift w/ recoil) ...

Article Quote - "a rule-of-thumb formula to achieve less recoil is to choose a heavier bullet with the smallest charge possible to achieve the desired PF."

https://tigersharkballistics.com.au/pages/recoil-heavy-or-light-bullets

Heavier projectiles also retain more energy the further they go. 

  • Like 1

Share this post


Link to post
Share on other sites

Empirical studies are called for.  Theoretical treatises are insufficient  to provide absolute proof.  I'll contribute to your commissioning fee in the amount of $0.02.  Hire all the consultants neede out of your commissioning fee, along with any necessary test equipment.  :ph34r:

  • Like 3

Share this post


Link to post
Share on other sites

 

PLUS ONE too Griff 

 

Empirical data is required.  All that "calculated" mumbo jumbo will crash and burn in the face of actual "rounds fired."

  • Like 2

Share this post


Link to post
Share on other sites

The faster is usually the less muzzle rise before the bullet exits the barrel and the lessor amount of gravity in flight.

Therefore it should impact a little lower.

J.M.

Share this post


Link to post
Share on other sites

Y'all forgot to factor in the difference in ballistic coefficient.

  • Like 1

Share this post


Link to post
Share on other sites

The other limiting factor is the minimum velocity.  At some point the larger bullets can’t go slow enough to meet the minimum velocity requirements and equal the power factor of the lighter bullets. 

Share this post


Link to post
Share on other sites

QUESTION:

If the lighter/faster bullet hits lower because it exits the muzzle before recoil effects its travel,

AND, the heavy/slower bullet hits higher because recoil is effecting its trajectory before it exits the muzzle,

wouldn't barrel length play a part of the equation?

 

How about a light faster bullet in a Long Barrel (lets say 7") vs. a heavy, slower bullet in a 3" barrel.

 

Looks like a whole new ball game to me if you factor in those items.

 

..........Widder

 

  • Like 1

Share this post


Link to post
Share on other sites
Posted (edited)

It's felt by many pards that a heavy hard alloy bullet will ring a target a little louder than a soft light-weight bullet.  That's why .36 caliber cap and ball shooters have so many misses called!   :o

 

The heavy bullet certainly is better on taking down knockdowns.

 

But you had better include that in your tests as well.

 

Good luck, GJ

Edited by Garrison Joe, SASS #60708
  • Thanks 1

Share this post


Link to post
Share on other sites

I could not find the thread regarding favorite loads for the 38 special.  I noticed some shooters really liked 125 grain bullets with 2.4 grains of clays vs 105 grain bullets with 2.9 grains of clays.   I am giving approximate loads since I could not find the thread.   Was wondering if it was personal preference or it had to do with how long the sight was off the target.  At close targets I have never noticed the difference.  When shooting at further away targets I have noticed the sights leaving the target on multiple shots with heavier loads.  Just wondering if the power factor was the same with a 125 vs 105 would you see the same lift or rise of the sights from one shot to the other.  I hope this better explains my point in the thread.  Any further ideas?

Share this post


Link to post
Share on other sites
Posted (edited)

KIRK,

that is some deep thinking.

Do you know the velocities of the rounds you are shooting of the 105/110   vs. the 125?

 

Velocity x weight divided by 1000 =  PF

Example:

105 at 800 fps has a PF of  84

125 at 750 fps has a PF of  93

 

I think your observance of heavier bullets causing your sights to move off target is a real occurrence.

 

This might not have helped answer your question, but I thought I would post it.

 

'CLANG' effect on a target with different bullet weights is a good lunch table discussion.

I shoot a .32 H&R in Cowboy competition.   

My bullet weights are 78, 82 and 100 grainers in the rifle.

My velocity with the 82 grainers is above 1200 fps because I like a fast bullet down range.

I have been told that my rifle 'clangs' are more audible than most others on the Posse and

more so than the mildly loaded .38 special stuff that most folks shoot.

 

Trying to filter in 'clang' effects is something you might have to experiment for yeself.

 

..........Widder

 

Edited by Widder, SASS #59054
  • Like 1
  • Thanks 1

Share this post


Link to post
Share on other sites

 

Around my neck of the woods, they switch spotters when I shoot my .36 Cap Guns.  I get the guys that cross intersections with a white cane.  They are also stone deaf.  They guys who spot for my .44s are much more adept at spotting.  Although, I did notice a dramatic difference when I switched from dead soft .36 balls to actual cast EPP UG - 36 Big Lube "Bullets" that weigh about 90 - 92 Gr.  With the same load as used with the soft round ball, the "Klang" factor is much improved.  Rather than a dull "thunk" the EPP UG - 36 arrives on target with a nice sharp 38ish "Klang."  Spotters also like the improvement of the EPP UG - 36.

 

There is also some class-room physics involved for the cause/effect of muzzle rise based on pay load and propellant not to forget to factor in torque effect on the projectile as imparted by launcher rifling.  Some rally heavy rocket science here.  I do think attempting to apply all the theoretical class room stuff is a waste of skull space.  My suggestion is to load up some ammo and to shoot at the little logo on the Pizza Box.  All the mathmitical preponderance of mythical numbers are worthless if you can't pull the trigger worth beans.   

  • Like 1
  • Haha 1

Share this post


Link to post
Share on other sites
Posted (edited)

I've noticed that spotter deficiency with my .36s also...   I once had all three spotters call for 4 misses on a dump target... there was only one lead splash on the target... TO TRIED to educate them...  so now I shoot for clean areas on the targets... far fewer called misses! :P

Edited by Griff
  • Like 1
  • Haha 1

Share this post


Link to post
Share on other sites
Posted (edited)

What are you looking for, as in the end result?  Badlands Bud and I did a huge amount of testing back in the day for the ultimate .38 round.  We defined that by both a combination of recoil management, accuracy, and fastest split times.  For both of us, a 125gr bullet at 825fps did the trick.  Bud's splits were fastest with this combination, as were mine (though his were much faster than mine - often fast enough the timer didn't pick it up).  We ran as light as 96gr bullets at 500fps and as heavy as 158gr bullets at 800 fps.  We burned a lot of ammo that day.

 

I have the data to back this up.

 

The reason I proposed this test was from watching splits at a steel challenge match.  Watching the splits for shooters with open guns shooting 38 super (or 9mm major) and then with similarly equipped .22's.  The splits were noticeably, and consistently faster with the higher recoil guns.

 

There's a lot of ergonomics and some kinesiology (sp?) in the "why".  But it boils down to the fact that our body's need the recoil and tactile sense, along with the energy of the recoil to get the muscles moving most efficiently.

 

The quest for less recoil will end up resulting in slower splits.

Edited by Doc Shapiro
  • Like 2
  • Thanks 3

Share this post


Link to post
Share on other sites

I tried some 125s gr at 2.9 of clays and compared them to my 105tc  with 2.9 grains of clays and I have to admit the 125 felt better and I shot better.  I will try

2.4 grains of clay's with the 125 and 3.1 grains of clays with the 100 grain and see how it feels.  They should have similiar power factors.  There are some very top shooters shooting 125's.  We will see if the hits are easier to hear.   I did a comparison test with Ray Heartless.  He was using 125s and I was using 105s.  I really enjoyed his load and thought the sound was more noticeable.  Thanks Doc

 

Share this post


Link to post
Share on other sites

I know when you buy a Ruger 357 Vaquero you have a sight up front.....a really tall sight that will have a pretty close POI with a 357 mag load. If you use it for cowboy 38's of 800 fps you need to file it down quiet a bit so that's what's happening if you exaggerate it. 

 

I know one of the faster pistols shooter's around here uses a LOT of power and a 125 because of what Doc said. 

Share this post


Link to post
Share on other sites
Posted (edited)
12 hours ago, Doc Shapiro said:

What are you looking for, as in the end result?  Badlands Bud and I did a huge amount of testing back in the day for the ultimate .38 round.  We defined that by both a combination of recoil management, accuracy, and fastest split times.  For both of us, a 125gr bullet at 825fps did the trick.  Bud's splits were fastest with this combination, as were mine (though his were much faster than mine - often fast enough the timer didn't pick it up).  We ran as light as 96gr bullets at 500fps and as heavy as 158gr bullets at 800 fps.  We burned a lot of ammo that day.

 

I have the data to back this up.

 

The reason I proposed this test was from watching splits at a steel challenge match.  Watching the splits for shooters with open guns shooting 38 super (or 9mm major) and then with similarly equipped .22's.  The splits were noticeably, and consistently faster with the higher recoil guns.

 

There's a lot of ergonomics and some kinesiology (sp?) in the "why".  But it boils down to the fact that our body's need the recoil and tactile sense, along with the energy of the recoil to get the muscles moving most efficiently.

 

The quest for less recoil will end up resulting in slower splits.

What we'd call testimonial and documentary evidence.   Legal in a court of law... and this member of the jury deems it sufficient.  

Edited by Griff

Share this post


Link to post
Share on other sites

When I was coach in the sport of wrestling I always watched the technique of the top wrestlers and based my practices on what wins the state championship and not the technique that gets them there.  I appreciate everyone's responses and hope there is more.  While I will not be changing loads prior to EOT I will always look in areas for improvement.  Doc, thanks for the tip and I will be loading up some 125s in the future.  Was the thread of favorite recipes taken off the wire?  I tried to search for it but with no luck.   

Share this post


Link to post
Share on other sites
6 minutes ago, Kirk James said:

When I was coach in the sport of wrestling I always watched the technique of the top wrestlers and based my practices on what wins the state championship and not the technique that gets them there.  I appreciate everyone's responses and hope there is more.  While I will not be changing loads prior to EOT I will always look in areas for improvement.  Doc, thanks for the tip and I will be loading up some 125s in the future.  Was the thread of favorite recipes taken off the wire?  I tried to search for it but with no luck.   

 

Nope, it's right here:

 

 

Share this post


Link to post
Share on other sites
8 hours ago, Kirk James said:

When I was coach in the sport of wrestling I always watched the technique of the top wrestlers and based my practices on what wins the state championship and not the technique that gets them there.  I appreciate everyone's responses and hope there is more.  While I will not be changing loads prior to EOT I will always look in areas for improvement.  Doc, thanks for the tip and I will be loading up some 125s in the future.  Was the thread of favorite recipes taken off the wire?  I tried to search for it but with no luck.   

 

Right before EOT is not the time to change anything.  After EOT is the time to change stuff for next year.

 

FWIW, my load now is 3.0gr of bullseye behind a 130gr TC from Badman Bullets.  But what's best for me may not be what's best for you.  Load up a bunch of different options, chrono and check the splits.  Both double taps, and splits between targets.  See what works best for you.

 

Doc

Share this post


Link to post
Share on other sites

Thanks Deuce and Doc-Be interested to test 125 grain bullets at 2.5, 2.7 and 2.9 against the 2.9 105s  and 3.1 100s.  They are all lubed bullets.  All loaded up for EOT.  Shooting the same loads we have shot for the last 6 years.  We have done fine as a family but there is always a desire to do better.  Any edge is better, just don't cross it.  I am taking the RO 2 course at EOT or I would be attending your shotgun school Deuce.  Missed it again.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.