Author Topic: Muzzle Jump affecting accuracy?  (Read 1188 times)

0 Members and 1 Guest are viewing this topic.

Offline elmerdeer

  • Trade Count: (0)
  • Member
  • *
  • Posts: 32
Muzzle Jump affecting accuracy?
« on: August 08, 2004, 04:18:02 AM »
I would like to know if muzzle jump affects accuracy or is the bullet already at the target? What is the best way to get accuracy off of sand bags at the range  (shooting procedure)?I shoot an encore .50 cal ml but trigger feels stiff. Thanks

Offline New Hampshire

  • Trade Count: (0)
  • A Real Regular
  • ****
  • Posts: 996
Muzzle Jump affecting accuracy?
« Reply #1 on: August 08, 2004, 05:07:18 AM »
Actualy recoil starts the minute the primer fires into the powder charge and the bullet begins moving.  The reason that it does not effect accuracy is because your regulate your sights to hit where you want them to and as long as you are using the same bullet weight and general velocity it does not matter when or where the barrel is vertically during recoil.  A good example is the old Colt .45 Peacmakers.  Sometimes you had to file down the front site to correspond with the recoil of your projectile weight (and many still do on the fixed site guns.)
Brian M.
NRA Life Member
Member Londonderry Fish and Game Club
Member North American Fishing Club
Member North American Hunting Club
Member New Hampshire Historical Society
Member International Blackpowder Hunting Association

Offline Redhawk1

  • Life time NRA Supporter.
  • GBO Supporter
  • Trade Count: (78)
  • Senior Member
  • *****
  • Posts: 10748
  • Gender: Male
Muzzle Jump affecting accuracy?
« Reply #2 on: August 08, 2004, 05:29:41 AM »
Recoil does affect your point of impact. If you shoot of a rest and shoot different holds and rifle placement on sand bags. It will affect you point on impact. Just changing the way you hold your gun will affect impact.

New Hampshire is 100% correct, recoil starts the minute the primer fires into the powder charge and the bullet begins moving.  :grin:
If  you're going to make a hole, make it a big one.
ΜΟΛΩΝ ΛΑΒΕ
Only two defining forces have ever offered to die for you,
Jesus Christ and the American G. I.
One died for your soul, the other for your freedom

Endowment Life Member of the NRA
Life Member NA

Offline longwinters

  • Moderators
  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 3070
Muzzle Jump affecting accuracy?
« Reply #3 on: August 08, 2004, 08:54:13 AM »
The previous guys are correct.  The bullet is long gone before you can react to the perceived/or real recoil. But at the same time recoil does make a difference. I think what you learn from recoil is this.  The at rest position of the rifle, after the recoil, will show you how your shooting form/follow thru is.  If your rifle is coming straight back then all is probably good.  If your rifle is jumping vertically more than a couple of inches you probably have to hard of a rest or have too little control over the forarm.  If it is jumping up and also to one side or the other you have a trigger pull problem or a pressure problem from your shoulder or setup.  Also I am learning that some of my problems have been my reaction while the shot is happening/at the trigger pull.  This would include flinching etc...

I am not a great shot but am learning thru experience.

Long
Life is short......eternity is long.

Offline KN

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1962
Muzzle Jump affecting accuracy?
« Reply #4 on: August 10, 2004, 01:46:00 PM »
Sorry but I gotta disagree with you cknight98, If the bullet had already left the barrel before any recoil or movement happened then it wouldn't matter how you held it. The other guys are right, recoil does matter.  KN

Offline Omega

  • Trade Count: (0)
  • Avid Poster
  • **
  • Posts: 236
Muzzle Jump affecting accuracy?
« Reply #5 on: August 11, 2004, 12:03:26 PM »
Quote from: cknight98
 its just that the muzzle jump itself doesnt really affect POI.  


Well, sorta....  :eek:  The slower the bullet the more it is affected by muzzle jump, simply because it is in the barrel longer. For example, when shooting a rifle like a 300 win mag zeroed at 100 yards with 150 grain bullets, people are surprised to see 180 grain bullets hit the target higher than the 150's. The answer is simply physics, the slower bullets are in the barrel longer and the muzzle has time to elevate enough to cause the shift in the impact point.  :D
"Beware all undertakings that require new clothes."

Offline KN

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1962
Muzzle Jump affecting accuracy?
« Reply #6 on: August 11, 2004, 12:27:15 PM »
Omega is exacly right. Muzzle jump starts long before the bullet exits the barrel. Pistols will show this more pronounced than rifles because of the slower velocities. If you take any known load and site it to hit zero, simply backing off the charge and having the bullet stay in the barrel longer will result in a higher inpact because the barrel is already moving in an upward direction. Most auto pistols have the barrel pointing at a downward angle when in battery and the sites are level across the top to compensate for the muzzle rise during recoil.  KN

Offline bgjohn

  • Trade Count: (0)
  • A Real Regular
  • ****
  • Posts: 602
Recoil/muzzle jump........
« Reply #7 on: August 11, 2004, 01:48:51 PM »
There are two components to recoil. The first begins the instant the bullet starts moving. The second is when the hot gases exit the barrel. By then the bullet is gone. Think about it. :wink:
JM
I know nothing. I am only a messenger.

Offline KN

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 1962
Muzzle Jump affecting accuracy?
« Reply #8 on: August 11, 2004, 05:22:16 PM »
Theres also a third. That bullet being "screwed" down the barrel will cause a twisting force on the barrel. Thats why if you are shooting off a bi-pod it has a tendency to lift one leg and jump a little side ways when you fire.  KN

Offline bgjohn

  • Trade Count: (0)
  • A Real Regular
  • ****
  • Posts: 602
Muzzle Jump affecting accuracy?
« Reply #9 on: August 12, 2004, 03:04:54 AM »
Quote from: KN
Theres also a third. That bullet being "screwed" down the barrel will cause a twisting force on the barrel. Thats why if you are shooting off a bi-pod it has a tendency to lift one leg and jump a little side ways when you fire.  KN



OK, I'll agree to that.
JM
I know nothing. I am only a messenger.

Offline New Hampshire

  • Trade Count: (0)
  • A Real Regular
  • ****
  • Posts: 996
Muzzle Jump affecting accuracy?
« Reply #10 on: August 12, 2004, 11:43:32 AM »
If anyone is really interested in learning more about subjects like this and ballistics in general try reading "Understanding Firearm Ballistics: Basic to Advanced Ballistics Simplified, Illustrated and Explained
Robert A. Rinker."  Very informative and he trys to make it easy for the average joe to understand.
Brian M.
NRA Life Member
Member Londonderry Fish and Game Club
Member North American Fishing Club
Member North American Hunting Club
Member New Hampshire Historical Society
Member International Blackpowder Hunting Association