It sounds like a difference in barrel twist could be the answer to why one guy loves a particular bullet for its fur friendliness and another hates it. Shawn Heydon,told me that his wildcat gunsmith told him that barrel twist effected how fast a bullet expands as it’s hitting the target. Shawn couldn’t remember if it was fast or slow twist that made the bullet blow up faster,but I would think it would have to be a faster twist that would cause a fragile vmax or similar bullet to crack open faster if this is indeed so. It would be great to get feedback as to barrel twist and muzzle velocity when someone is describing bullet performance on fur. Many times I have read posts were someone reports great performance with a particular bullet and then the next guy says he has splashes. If people begin stating twist and if possible muzzle velocity It may shed some valuable light on the subject. A couple pages of posts with proper data could be a real learning experience. What say you?
Is barrel twist difference the reason?
- Thread starter J.Mark
- Start date
OldTurtle
Moderator - Deceased
There is a point where the rate of spin can negatively affect a lighter weight bullet at higher velocities, especially the rapid fragmentation varieties...
I used to have a slow twist (1/14) .223 that allowed me to push the 40gr ballistic tips almost to the speed of my .204s with excellent results and one of the side benefits was a very flat trajectory that I couldn't get with a heavier bullet...However, the twist rate restricted me to 55gr bullets for accuracy purposes...
On the same line of thought, pushing a light weight bullet through a fast twist barrel (1/6.5 or 1/7) at high speeds can cause the bullet to disintegrate before reaching the intended target...I have some Hornady Super Explosive bullets that are restricted to 3200 fps, regardless of twist, due to the same expectations..
I would tend to agree that the faster a bullet spins, the more the energy transfer, but have no documentation to back up that feeling...
I used to have a slow twist (1/14) .223 that allowed me to push the 40gr ballistic tips almost to the speed of my .204s with excellent results and one of the side benefits was a very flat trajectory that I couldn't get with a heavier bullet...However, the twist rate restricted me to 55gr bullets for accuracy purposes...
On the same line of thought, pushing a light weight bullet through a fast twist barrel (1/6.5 or 1/7) at high speeds can cause the bullet to disintegrate before reaching the intended target...I have some Hornady Super Explosive bullets that are restricted to 3200 fps, regardless of twist, due to the same expectations..
I would tend to agree that the faster a bullet spins, the more the energy transfer, but have no documentation to back up that feeling...
Jack Roberts
Moderator - Deceased
No question about it.
Higher RPM makes bullets expand faster.
It is easy to see if you have 2 people shooting colony varmints with the same caliber but different twists. The faster twist gives significantly more air time and carnage.
Jack
Higher RPM makes bullets expand faster.
It is easy to see if you have 2 people shooting colony varmints with the same caliber but different twists. The faster twist gives significantly more air time and carnage.
Jack
Ackman
New member
Originally Posted By: J.Mark Shawn Heydon,told me that his wildcat gunsmith told him that barrel twist effected how fast a bullet expands as it’s hitting the target. Shawn couldn’t remember if it was fast or slow twist that made the bullet blow up faster,but I would think it would have to be a faster twist that would cause a fragile vmax or similar bullet to crack open faster if this is indeed so.
This Shawn guy doesn't have clue does he? So why even repeat what someone says his gunsmith told him, when he can't even remember what it was.
Faster twist is more explosive. Shoot a couple 223's side by side, one 14 twist the other a 9 or 10 twist and it's apparent. That doesn't really matter, varmint bullets blow up a small critter just fine when shot through a 14 twist barrel. The downside to faster twists is that the accuracy window is narrower.....they're more finicky about loads.
This Shawn guy doesn't have clue does he? So why even repeat what someone says his gunsmith told him, when he can't even remember what it was.
Faster twist is more explosive. Shoot a couple 223's side by side, one 14 twist the other a 9 or 10 twist and it's apparent. That doesn't really matter, varmint bullets blow up a small critter just fine when shot through a 14 twist barrel. The downside to faster twists is that the accuracy window is narrower.....they're more finicky about loads.
I wouldn't say Shauwn dosnt have a clue.What he does know is that out out of his Akley improved 243 using rem. 80 gr.psp the hundreds of coyotes he's killed have had very little damage.I brought the subject up to him of vmax bullets working very well for one person and very poorly for another.Your right he didnt know what twist his gunsmith refered to,but then with the bullet Shawn uses it doesn't realy matter.For those who use vmax type bullets the whole twist theory might be a big help in explaining one person having consistant fur friendly results, while the next guy is in splash city.
Winny Fan
New member
Originally Posted By: J.Mark.......For those who use vmax type bullets the whole twist theory might be a big help in explaining one person having consistant fur friendly results, while the next guy is in splash city.
It definitely might. Another factor in bullet performance is where the animal is hit. A hunter who typically slips a varmint type bullet between the ribs on a coyote will generally have great luck with a certain bullet. If he hits a coyote on the point of the shoulder with the same bullet, poor bullet performance - including bullet splash - might occur.
It definitely might. Another factor in bullet performance is where the animal is hit. A hunter who typically slips a varmint type bullet between the ribs on a coyote will generally have great luck with a certain bullet. If he hits a coyote on the point of the shoulder with the same bullet, poor bullet performance - including bullet splash - might occur.