Sabot blow by

Modern Muzzleloading Forum

Help Support Modern Muzzleloading Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Steelheader323

Well-Known Member
*
Joined
Dec 10, 2015
Messages
850
Reaction score
783
Maybe that's not the correct term or phrase for what I'm speaking of but basically what I'm talking about is when the gases from the powder charge pass by the bullet/sabot before it exits the barrel. How can I test this without a chronograph?

Reason for ask my is because at the range this past weekend I was dialed my in my omega, my go to load has been a 250 grain xtp with a black crush rib sabot pushed by 90grains of bh209. This load does very well in my gun and I get 1.5" groups @ 100 yards if I do my part. It loads evenly down the barrel and seems to be a snug enough fit. Now while at the range i tried the Federal bor lock bullet 270 grain trophy copper. It consistently shot 4 inches higher tHan my xtp does , I found it strange that a slightly heavier bullet would shoot that much higher which leads me to think I'm. It getting a good deal with the xtp and crush rib sabot, even tho it's very accurate. It worries me that I may be losing velocity, any thoughts on how to test this? Or am I being a worry wart?


Sent from my iPhone using Tapatalk
 
Re: Sabot blow by

The bor lock being sabotless (skirted) can explain the difference in POI. How was the fit with the bore lock? I don't think there's any worry with the xtp. They are accurate in a number of my guns. Your accuracy suggests no problem with escaping gasses. The black crush rib will do the job and seal the bore and expand into the bore grooves when you pull the trigger. Your not a worry wart. Your question is a good one.
 
They loaded similar but the bor lock seemed to be sticky in some spots maybe because of the material that the skirt is made of?


Sent from my iPhone using Tapatalk
 
Re: Sabot blow by

The heavier the bullet, the longer it takes to get out of the barrel. So my theory is recoil Is your culprit.
 
I was firing the gun from a lead sled, not sure how much it rises when firing, never really paid attention I guess lol


Sent from my iPhone using Tapatalk
 
Re: Sabot blow by

Time in bore is important. Also, friction is important. Similar weight bullets one in a sabot, the other full caliber, the full caliber will be slower due to bore friction.
 
Re: Sabot blow by

Grouse said:
The heavier the bullet, the longer it takes to get out of the barrel. So my theory is recoil Is your culprit.

Or the heavier bullet is longer and therefore should have a higher BC and a higher gyroscopic stability imo. There's the "a body in motion tends to stay in motion" rule and the momentum of the heavier bullet could be the reason for a higher POI if it's extending the apex of the trajectory a bit within 100 yards.
 
Re: Sabot blow by

Like has already been said. Heavier slower bullet spends more time in bore, barrel rises more from recoil before it spits it out, resulting in a higher POI. Happens a lot. Nothing to worry about, as long as it's shooting groups.
 
Wouldn't this greatly effect poi if someone were to sight their rifle in using a lead sled compared to shooting free handed in the field?


Sent from my iPhone using Tapatalk
 
Re: Sabot blow by

Steelheader323 said:
Wouldn't this greatly effect poi if someone were to sight their rifle in using a lead sled compared to shooting free handed in the field?
I wonder about this, too. I've been having trouble getting a Vortek Strikerfire rifle to group with anything. I've been shooting from a lead sled and I did notice how much barrel jump it had when shooting. Way more than my CVA rifles and MK85. Probably because it is lighter and has different stock/barrel geometry and balance. I try to hold it firmly to minimize the jump but you can't stop it all. I wonder now if that is why it won't group. I'm going to shoot it with a front rest only, and a rear bag, as soon as I get a chance and see if it makes a difference. I'm thinking it will.
 
Re: Sabot blow by

Steelheader323 said:
Wouldn't this greatly effect poi if someone were to sight their rifle in using a lead sled compared to shooting free handed in the field?
Sent from my iPhone using Tapatalk

Normally no. Lead sleds are great for determining what the rifle will or won't do. "Free handed" (no rests?) is a whole different ball game. Its then entirely the shooter.

I shoot much heavier loads than most shoot or will ever shoot, with a LOT of recoil. From the sled, or off the front/rear bag, it shoots the same. It also shoots the same when just using a front rest and off the shoulder only, after setting it in a sled.
Bullets moving out a barrel are measured in milliseconds. Different brand bullets of even the same weight and while using sabots, can very well shoot higher/lower and still group. Nature of some beasts. If they group, adjust when needed.
 
Re: Sabot blow by

Lead Sleds are notorious for killing cheap scopes and stocks on hard kickers. If the rifle will not group, you've probably already trashed your scope. Check your stock bolts to make sure they are still tight too.
 
Groups for me have been just fine, just a raised poi was all that had me wondering


Sent from my iPhone using Tapatalk
 
Re: Sabot blow by

sabinajiles said:
............... I try to hold it firmly to minimize the jump but you can't stop it all. I wonder now if that is why it won't group.............
You may be anticipating the recoil; that can't have a happy ending. Trying to stop the rifle from jumping, may be why you aren't happy with groups. Relax, don't think about jump, hold the rifle firm, but not tensed........may or may not help groups.
 
Re: Sabot blow by

ronlaughlin said:
sabinajiles said:
............... I try to hold it firmly to minimize the jump but you can't stop it all. I wonder now if that is why it won't group.............
You may be anticipating the recoil; that can't have a happy ending. Trying to stop the rifle from jumping, may be why you aren't happy with groups. Relax, don't think about jump, hold the rifle firm, but not tensed........may or may not help groups.
The extreme barrel jump is just a problem with this Vortek from the lead sled, not any of my other rifles. For some reason it reacts to the recoil by going up, not back. It jumps so violently it would literally jump right out of the front rest cradle if not restrained. It's a fairly new rifle but I have yet to find any load combination that will group under 3-4 inches at 100 yds, most being worse than that. I am looking for any answers before I contact Traditions about a bad barrel. Reading this thread reminded me that I noticed the heavier recoiling loads, those with heavier bullets and more powder, are producing the largest groups and flyers are usually high and left.
 
Re: Sabot blow by

sabinajiles said:
ronlaughlin said:
sabinajiles said:
............... I try to hold it firmly to minimize the jump but you can't stop it all. I wonder now if that is why it won't group.............
You may be anticipating the recoil; that can't have a happy ending. Trying to stop the rifle from jumping, may be why you aren't happy with groups. Relax, don't think about jump, hold the rifle firm, but not tensed........may or may not help groups.
The extreme barrel jump is just a problem with this Vortek from the lead sled, not any of my other rifles. For some reason it reacts to the recoil by going up, not back. It jumps so violently it would literally jump right out of the front rest cradle if not restrained. It's a fairly new rifle but I have yet to find any load combination that will group under 3-4 inches at 100 yds, most being worse than that. I am looking for any answers before I contact Traditions about a bad barrel. Reading this thread reminded me that I noticed the heavier recoiling loads, those with heavier bullets and more powder, are producing the largest groups and flyers are usually high and left.

The extreme jump may be contributed to the stock and its relationship (alignment) to the barrel. I helped a owner setup his and honestly, I can't remember the barrel/stock alignment. One thing for certain, if you try holding down the barrel, it can give erratic groups or POI for the shooter. We, you and I, can't hold down the barrel with the same exact force each time we fire a round. Removing all weight from the sled, allowing the rifle to recoil in a straighter line rearward might help. Better yet, shoot the rifle from just a front rest and a rear bag. The rifle should recoil in a straighter line rearward. Yes, the shooter will need to learn to absorb properly. Just purchase a PAST recoil pad, which works.

Find a way to keep your free hand away from the forearm and let the rifle recoil in a straighter line rearward. There are shooters on this site, probably reading this, that are very accurate shooters. Two of us can shoot charges much heavier than mass produced rifles are capable of. I can name the other, as I've watched him shoot and competed with him, bestill. Even with these very heavy charges, we're shooting off front rests only, not holding down the forearm with our free hand. My rifle is controlled, I've watched bestill control his rifle, which he does pretty darn good by the way :prayer:
 
Re: Sabot blow by

ENCORE50A said:
sabinajiles said:
ronlaughlin said:
You may be anticipating the recoil; that can't have a happy ending. Trying to stop the rifle from jumping, may be why you aren't happy with groups. Relax, don't think about jump, hold the rifle firm, but not tensed........may or may not help groups.
The extreme barrel jump is just a problem with this Vortek from the lead sled, not any of my other rifles. For some reason it reacts to the recoil by going up, not back. It jumps so violently it would literally jump right out of the front rest cradle if not restrained. It's a fairly new rifle but I have yet to find any load combination that will group under 3-4 inches at 100 yds, most being worse than that. I am looking for any answers before I contact Traditions about a bad barrel. Reading this thread reminded me that I noticed the heavier recoiling loads, those with heavier bullets and more powder, are producing the largest groups and flyers are usually high and left.

The extreme jump may be contributed to the stock and its relationship (alignment) to the barrel. I helped a owner setup his and honestly, I can't remember the barrel/stock alignment. One thing for certain, if you try holding down the barrel, it can give erratic groups or POI for the shooter. We, you and I, can't hold down the barrel with the same exact force each time we fire a round. Removing all weight from the sled, allowing the rifle to recoil in a straighter line rearward might help. Better yet, shoot the rifle from just a front rest and a rear bag. The rifle should recoil in a straighter line rearward. Yes, the shooter will need to learn to absorb properly. Just purchase a PAST recoil pad, which works.

Find a way to keep your free hand away from the forearm and let the rifle recoil in a straighter line rearward. There are shooters on this site, probably reading this, that are very accurate shooters. Two of us can shoot charges much heavier than mass produced rifles are capable of. I can name the other, as I've watched him shoot and competed with him, bestill. Even with these very heavy charges, we're shooting off front rests only, not holding down the forearm with our free hand. My rifle is controlled, I've watched bestill control his rifle, which he does pretty darn good by the way :prayer:


I totally disagree with your shooting style for a hunter. You need to hold any gun on the bench like you would hunting. But like you stated, don't hold the barrel hold the forearm. Before hunting season I verify poi on the bench. After that I shoot my gun in the woods. Resting on tree limb, off my knee, laying down etc.
 
Re: Sabot blow by

Grouse said:
ENCORE50A said:
sabinajiles said:
The extreme barrel jump is just a problem with this Vortek from the lead sled, not any of my other rifles. For some reason it reacts to the recoil by going up, not back. It jumps so violently it would literally jump right out of the front rest cradle if not restrained. It's a fairly new rifle but I have yet to find any load combination that will group under 3-4 inches at 100 yds, most being worse than that. I am looking for any answers before I contact Traditions about a bad barrel. Reading this thread reminded me that I noticed the heavier recoiling loads, those with heavier bullets and more powder, are producing the largest groups and flyers are usually high and left.

The extreme jump may be contributed to the stock and its relationship (alignment) to the barrel. I helped a owner setup his and honestly, I can't remember the barrel/stock alignment. One thing for certain, if you try holding down the barrel, it can give erratic groups or POI for the shooter. We, you and I, can't hold down the barrel with the same exact force each time we fire a round. Removing all weight from the sled, allowing the rifle to recoil in a straighter line rearward might help. Better yet, shoot the rifle from just a front rest and a rear bag. The rifle should recoil in a straighter line rearward. Yes, the shooter will need to learn to absorb properly. Just purchase a PAST recoil pad, which works.

Find a way to keep your free hand away from the forearm and let the rifle recoil in a straighter line rearward. There are shooters on this site, probably reading this, that are very accurate shooters. Two of us can shoot charges much heavier than mass produced rifles are capable of. I can name the other, as I've watched him shoot and competed with him, bestill. Even with these very heavy charges, we're shooting off front rests only, not holding down the forearm with our free hand. My rifle is controlled, I've watched bestill control his rifle, which he does pretty darn good by the way :prayer:


I totally disagree with your shooting style for a hunter. You need to hold any gun on the bench like you would hunting. But like you stated, don't hold the barrel hold the forearm. Before hunting season I verify poi on the bench. After that I shoot my gun in the woods. Resting on tree limb, off my knee, laying down etc.

I think before he starts hunting, he's actually looking towards improving his groups, and understanding why he has such a "violent" jump. His stock/barrel alignment "may" contribute. To check that, most do that from a bench, getting the rifle to shoot as expected or intended first. Once the rifle has proven itself, then work on hunting shots. If one is just looking for hunting accuracy, then he could probably quit now. But he stated he's trying to understand and better his 3-4" groups at 100yds.
 
Re: Sabot blow by

This isn't a rifle with which I am hunting. I have been hunting for 50 years and am completely aware of how to hold a rifle for hunting. I bought the Vortek on a whim and as ENCORE50A said, I am just trying to figure out why I can't get it to shoot. My apologies for hijacking this thread about this. I only responded originally because of the comment wondering if a lead sled could change the POI and my own thoughts that it possibly could, at least in some instances. I will determine that for my case whenever I get a chance to shoot from the bench again.
 
Back
Top