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Are solid/monolithic bullets more finicky than jacketed?

odoylerules

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Apr 25, 2017
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I was told this from a builder today. I’m starting to research things for a future .375 barrel (37XC for my Desert Tech). It’s going to be for long range fun and competition, not hunting. I understand it’s something you kinda have to decide ahead of time because of the big differences in twist rates and freebore setups.
I’ve read about how great Hammer bullets are and how easy to tune. That’s why I was so confused when I heard that today.
 
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This is Just what I have seen.
I see some difference between them, depending the solids mfg an the barrels true size not just advertised. Remember when you hit the bullet in the ass with that amount of pressure a jacket/lead combo will most always conform to that bore if it has a half ass seal from the get go. I don't find that to be the case with solids. Some solid mfg'ers I have used fit my bore/barrel w/o issue an very little gas blow by, some do not. No matter the jacket/lead core combo I have not found that to be an issue. All solid mfgs get the first 3 decimal places right but the 4th can be from zero to 9.

An extra FYI,... I see the 4th place number play a huge roll in jacketed subsonic's as well. Not so much in home rolled cast loads. Barrel vs bullet combos are a rabbit hole sometimes,...
 
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If you are playing with the little guns, jacketed bullets do just fine. As you go up in bore, jacketed bullet start to suck it pretty quick. In the end, even if you can manage to make them perfectly, they have huge bearing surfaces compared to the solids and simply can't be pushed as fast safely. At 50 cal the options are Hornady and another bullet that I won't name that can barely manage a degree of spread. 50 Cal Amax is about the most finicky thing I've heard of. If you sort them by weight then by ogive then spin then to check stability, they fly well out of a 3 groove pac nor barrel at 2650 fps and they eat shit if you deviate from that path. There is a reason the have disappeared from the FCSA match line. None of the solids I've shot have required so much work. I don't even bother to weigh them anymore. Extreme spread was .2 grains the last time I checked.

If you want a perfect bullet, slug your barrel and mic it out. Have bullets made to fit your gun. Making a custom swaged bullet is tens of thousands. Making a custom CNC bullet is a few lines of code.

-Alex
 
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I've discussed this extensively in other posts, but the fit of the bearing surface (or driving band in the solids world) to the groove diameter of your barrel is critical to prevent gas leak by and ultimately have good results down range. Solids do not conform to your barrel's groove diameter on initial start pressure as a jacketed lead bullet will. Barrel manufacturers by default, make their groove diameters on the plus side of the nominal tolerance; for safety sake. Lets use your .375 cal as an example here. Brand X barrel will make barrels with groove diameters between 0.3750 and 0.3756. Most will aim for the middle of those numbers. Never will you see a purposely made barrel that is small here (less than 0.3750) unless it comes will all kinds of liability waivers, as the potential for over pressure grows as the numbers get smaller.
Now since the solid will not expand even a little bit to reach that 0.000x variance, it is crucial that the bullet be sized to fit that groove. The key is to know what your groove diameter is. Bartlein will air gauge barrels to 4 places if you tell them you will be using solids; they are doing it for us on everything we order. Further, we have the ability to measure the slug cut from the muzzle end of your barrel when crowned. Using our CMM, we can determine all kinds of cool dimensional characteristics about your lands and grooves, but most importantly, we measure your groove diameter very accurately. We can then supply you with projectiles that match those numbers.
I will also respond Gunfighter14e2's statement: "All solid mfgs get the first 3 decimal places right but the 4th can be from zero to 9." by saying not true at all. I challenge you to find a Flatline in any given box or package that has more than a .0001 spread anywhere. In fact, knowing that our allowance on any lot is +/- 0.00005, I would venture that most do not have the proper tools to measure the slight variance that we do allow. You won't see them with a standard micrometer and you surely won't see it with calipers.
 
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I will also respond Gunfighter14e2's statement: "All solid mfgs get the first 3 decimal places right but the 4th can be from zero to 9." by saying not true at all. I challenge you to find a Flatline in any given box or package that has more than a .0001 spread anywhere. In fact, knowing that our allowance on any lot is +/- 0.00005, I would venture that most do not have the proper tools to measure the slight variance that we do allow. You won't see them with a standard micrometer and you surely won't see it with calipers.


Lol... This reminds me of an interaction I saw between Lynn and someone he had made bullets for. Went something like, "You are seriously trying to tell me the bullets I machine to 1/10000th tolerances are the wrong size because you measured them with a $20 Chinese caliper?" Lynn maintained a list of people he would no longer sell bullets to...

-Alex
 
I've discussed this extensively in other posts, but the fit of the bearing surface (or driving band in the solids world) to the groove diameter of your barrel is critical to prevent gas leak by and ultimately have good results down range. Solids do not conform to your barrel's groove diameter on initial start pressure as a jacketed lead bullet will. Barrel manufacturers by default, make their groove diameters on the plus side of the nominal tolerance; for safety sake. Lets use your .375 cal as an example here. Brand X barrel will make barrels with groove diameters between 0.3750 and 0.3756. Most will aim for the middle of those numbers. Never will you see a purposely made barrel that is small here (less than 0.3750) unless it comes will all kinds of liability waivers, as the potential for over pressure grows as the numbers get smaller.
Now since the solid will not expand even a little bit to reach that 0.000x variance, it is crucial that the bullet be sized to fit that groove. The key is to know what your groove diameter is. Bartlein will air gauge barrels to 4 places if you tell them you will be using solids; they are doing it for us on everything we order. Further, we have the ability to measure the slug cut from the muzzle end of your barrel when crowned. Using our CMM, we can determine all kinds of cool dimensional characteristics about your lands and grooves, but most importantly, we measure your groove diameter very accurately. We can then supply you with projectiles that match those numbers.
I will also respond Gunfighter14e2's statement: "All solid mfgs get the first 3 decimal places right but the 4th can be from zero to 9." by saying not true at all. I challenge you to find a Flatline in any given box or package that has more than a .0001 spread anywhere. In fact, knowing that our allowance on any lot is +/- 0.00005, I would venture that most do not have the proper tools to measure the slight variance that we do allow. You won't see them with a standard micrometer and you surely won't see it with calipers.
Dan, thanks for taking the time to explain this concept to me. I still have a lot to learn obviously. I’m gonna be jumping into this world this year and I trying to research as much as possible in order to hit the ground running
 
Though I don't have much experience with the ELR style solids, I will say the the same things mentioned above are true with solid hunting bullets like Barnes and Hornady GMX. They often shoot very poorly in CHF barrels because the CHF process can produce minor variations in bore diameter, tight and loose spots if you will. They will squeeze down in the tight spots (provided it's nothing too extreme), but will not spring back for the loose spots and you get wobble, gas blowby, etc... And accuracy can fall completely off.

The only experience I have with the ELR solids were some 750-800gr .50 cal solids about 10 years ago. The rifle was the limiting factor in that case and I didn't make it very far-- opted just to shoot API and APIT for fireworks.
 
I've discussed this extensively in other posts, but the fit of the bearing surface (or driving band in the solids world) to the groove diameter of your barrel is critical to prevent gas leak by and ultimately have good results down range. Solids do not conform to your barrel's groove diameter on initial start pressure as a jacketed lead bullet will. Barrel manufacturers by default, make their groove diameters on the plus side of the nominal tolerance; for safety sake. Lets use your .375 cal as an example here. Brand X barrel will make barrels with groove diameters between 0.3750 and 0.3756. Most will aim for the middle of those numbers. Never will you see a purposely made barrel that is small here (less than 0.3750) unless it comes will all kinds of liability waivers, as the potential for over pressure grows as the numbers get smaller.
Now since the solid will not expand even a little bit to reach that 0.000x variance, it is crucial that the bullet be sized to fit that groove. The key is to know what your groove diameter is. Bartlein will air gauge barrels to 4 places if you tell them you will be using solids; they are doing it for us on everything we order. Further, we have the ability to measure the slug cut from the muzzle end of your barrel when crowned. Using our CMM, we can determine all kinds of cool dimensional characteristics about your lands and grooves, but most importantly, we measure your groove diameter very accurately. We can then supply you with projectiles that match those numbers.
I will also respond Gunfighter14e2's statement: "All solid mfgs get the first 3 decimal places right but the 4th can be from zero to 9." by saying not true at all. I challenge you to find a Flatline in any given box or package that has more than a .0001 spread anywhere. In fact, knowing that our allowance on any lot is +/- 0.00005, I would venture that most do not have the proper tools to measure the slight variance that we do allow. You won't see them with a standard micrometer and you surely won't see it with calipers.
Dan, I tried to PM you but it wouldn’t let me. Forgive the ignorance I have about this as I’m new to this part of the sport.
Let’s say I buy a a barrel to chamber up for the 37xc I’m planning for my desert tech. I was thinking of getting one from ES tactical. I believe they use blanks from K&P Barrels. How would I get that exact bore dimensions to give you? Would I trust ES, or send the barrel to you guys?
Thanks
 
From a hunters perspective, Barnes bullets have almost always shot way better than jacketed bullets in my 3 hunting rifles. Tried and tried to get ELD or Accubond loads to group as well as a TSX or LRX with minimal success.

Out of my serbu I have used AMAX 50bmg and they were stupid accurate.

Although I don’t if holds past a couple hundred yards. At 100 to 500 the all copper just flies like a laser.
 
Dan, I tried to PM you but it wouldn’t let me. Forgive the ignorance I have about this as I’m new to this part of the sport.
Let’s say I buy a a barrel to chamber up for the 37xc I’m planning for my desert tech. I was thinking of getting one from ES tactical. I believe they use blanks from K&P Barrels. How would I get that exact bore dimensions to give you? Would I trust ES, or send the barrel to you guys?
Thanks

Slugging the bore is the classic was to do it. Get a slightly overbore lead ball, a wooden dowel and a hammer. Don't expect it to go quickly... Accuracy of this is slightly questionable but it isn't a bad way to get a pretty good idea.

Casting in cerosafe gets you a pretty good read on it too but you need to cast down past the end of and modifications to the lands that the reamer is making.

Air gauging or laser scanning is the right way to do it but you aren't going to be doing that at home. If Kenny is making your barrel ask him about it. For all I know he has the gear to measure on hand.

-Alex
 
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Dan, I tried to PM you but it wouldn’t let me. Forgive the ignorance I have about this as I’m new to this part of the sport.
Let’s say I buy a a barrel to chamber up for the 37xc I’m planning for my desert tech. I was thinking of getting one from ES tactical. I believe they use blanks from K&P Barrels. How would I get that exact bore dimensions to give you? Would I trust ES, or send the barrel to you guys?
Thanks
Pardon the delayed response, my Hide account had issues with me changing email addresses.
Most folks don't have the capacity to measure the groove diameters accurately. There are basically two ways to get us the dimensions. If the barrel mfg has the capacity to air gauge the barrel and measure to 4 places, we can certainly use that number. Not sure if K&P can do that or not. The other is as I explained in my first post; send us the slug cut off from the muzzle when the barrel is crowned. Ask your smith to save this and have it sent here for measurement. Once we have it, we will inspect it using our coordinate measuring machine.
 
Lol... This reminds me of an interaction I saw between Lynn and someone he had made bullets for. Went something like, "You are seriously trying to tell me the bullets I machine to 1/10000th tolerances are the wrong size because you measured them with a $20 Chinese caliper?" Lynn maintained a list of people he would no longer sell bullets to...

-Alex

I am a Lynn but not from Wyoming and I am interested in this post if you have it available?

And Ken Eng who is a FCSA active member and shooter doesn't seem to have any problems with his A-Max bullets at Coalinga recently or at our 2000 yard matches.

When I read about finicky bullets I never hear about diameter issues to xxxx places it's usually seating depth and accuracy.
When Berger brought out the VLD line everybody was talking about how finicky they were.
 
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This was a conversation I saw in raton about a decade ago. As far as I know Lynn McMurdo never participated in online discussions.

Amax can shoot well, but it takes vastly more work than solids do and the records show that solids perform better. As far as I know there are no fcsa group or score records that have been shot with amax. The possible exception is the unlimited first 50-5x but I think Bryan only used the ALS in hunter and heavy.

-Alex
 
I think when you have choices to choose from it helps skew the numbers.
 
I recommend that you take Dan Warner up on his offer to measure your barrel groove ID with his CMM equipment, especially if your barrel has an odd number of lands and grooves. Cut off the extra 1-inch at the muzzle end of your blank which was left on for use while machining the blank in fitting it to your rifle. That extra inch is usually not hand-lapped all the way to the end of the blank, but its back end should be OK to measure. Saw off the extra inch using a fine-tooth blade rather than parting it off in a lathe, which is a higher-stress operation and mechanically stress relieves the hoop stresses implanted in button-rifled blanks, allowing the bore to expand on each side of the cut.

Mitutoyo makes good 4.5-decimal 1-inch digital micrometers which are not too expensive. Keep everything clean or you might be measuring your fingerprints.

Dan will soon be making my next batch of prototype copper ULD bullets for test-firing in 338 caliber. They will have 0.0006-inch over-diameter rear driving/sealing bands and will be base-drilled to expand more for complete gas sealing. I believe they will work, but Dan is skeptical. We shall see.

I am attaching my latest treatise on Interior Ballistics with Copper Bullets. The hardness of the copper used is critically important in making solid copper bullets. Copper is a fully strain-hardening material, which complicates things considerably.

Jim Boatright
 

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  • Interior Ballistics with Copper Bullets V04.pdf
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I was told this from a builder today. I’m starting to research things for a future .375 barrel (37XC for my Desert Tech). It’s going to be for long range fun and competition, not hunting. I understand it’s something you kinda have to decide ahead of time because of the big differences in twist rates and freebore setups.
I’ve read about how great Hammer bullets are and how easy to tune. That’s why I was so confused when I heard that today.

O'Doyle, I would suggest a 7-inch twist button-rifled barrel from Gary Schneider using his P5 rifling pattern for shooting 375-caliber solids well. I notice that Bryan Litz is now recommending that twist rate for shooting his new 375-caliber solids, too.

Jim Boatright
 
O'Doyle, I would suggest a 7-inch twist button-rifled barrel from Gary Schneider using his P5 rifling pattern for shooting 375-caliber solids well. I notice that Bryan Litz is now recommending that twist rate for shooting his new 375-caliber solids, too.

Jim Boatright
How do you like the Bartlien barrels compared to the Schneider? I went with a Bartlien 7 twist 5R for my 375 I'm building.
 
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After reading the whole thread... and because I have no idea.

Would "solids" perform "better or worse" in a 5R barrel.

I use the hash marks, because I realize there are a lot of variables involved. But, lets just say the conventional rifled barrel v. the 5R... and both are very well made.

Would the 5R rifling be better ?... at least as per the "math" penciled out.
 
I have a heavy varmint Bartlein 6.6-inch twist 338 barrel rifled in Boots Obermeyer's 5R pattern fitted in 338 LM, but have not yet fully evaluated it. We still need to fit and time the LAW muzzle brake made by Mic McPherson and which also allows solid attachment of a Magneto-Speed chronograph. The 5-inch twist 6.5 mm 5R barrel blank I ordered from Bartlein several months ago is due next month. The only real difference I expect to see is that the stress-free cut-rifled barrels from Bartlein will expand internally about 50-percent more in firing than would an equivalent button-rifled Schneider barrel with its residual hoop stresses resulting from the buttoning. That extra internal barrel expansion is no problem shooting lead-cored bullets, but can cause barrel obturation problems shooting non-deforming copper bullets.

All of my 375-caliber rifles are hunting rifles chambered in 375 H&H Magnum.

Jim Boatright
 
I have a heavy varmint Bartlein 6.6-inch twist 338 barrel rifled in Boots Obermeyer's 5R pattern fitted in 338 LM, but have not yet fully evaluated it. We still need to fit and time the LAW muzzle brake made by Mic McPherson and which also allows solid attachment of a Magneto-Speed chronograph. The 5-inch twist 6.5 mm 5R barrel blank I ordered from Bartlein several months ago is due next month. The only real difference I expect to see is that the stress-free cut-rifled barrels from Bartlein will expand internally about 50-percent more in firing than would an equivalent button-rifled Schneider barrel with its residual hoop stresses resulting from the buttoning. That extra internal barrel expansion is no problem shooting lead-cored bullets, but can cause barrel obturation problems shooting non-deforming copper bullets.

All of my 375-caliber rifles are hunting rifles chambered in 375 H&H Magnum.

Jim Boatright

@Jim Boatright
Thank You, I have most all of the Precision Shooting magazines and a few of the Books, all purchased years ago.. and clearly, I under appreciated the wealth of knowledge available at the time.
( Most likely it was completely over my head )

But know most all of it makes sense.

Looks like I have quite a bit of reading to catch up on... I do appreciate your sharing of your ballistic knowledge and wisdom.

Should our paths ever cross... remind me, I owe you a dinner or drink ( or more )

Not just for the knowledge... but for reminding me of all those stashed away copies of Precision Shooting magazines... Lol

Frankly, its kind of like a profoundly surprising Christmas in Feb.

Again, Thank You
 
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After reading the whole thread... and because I have no idea.

Would "solids" perform "better or worse" in a 5R barrel.

I use the hash marks, because I realize there are a lot of variables involved. But, lets just say the conventional rifled barrel v. the 5R... and both are very well made.

Would the 5R rifling be better ?... at least as per the "math" penciled out.
CUTTING EDGE WARNER AND BADLANDS WILL ALL SHOOT FINE IN THE R5 BARREL IF YOUR TWIST IS CORRECT AND YOU DEVLOP PROPER LOADS
 
I have a heavy varmint Bartlein 6.6-inch twist 338 barrel rifled in Boots Obermeyer's 5R pattern fitted in 338 LM, but have not yet fully evaluated it. We still need to fit and time the LAW muzzle brake made by Mic McPherson and which also allows solid attachment of a Magneto-Speed chronograph. The 5-inch twist 6.5 mm 5R barrel blank I ordered from Bartlein several months ago is due next month. The only real difference I expect to see is that the stress-free cut-rifled barrels from Bartlein will expand internally about 50-percent more in firing than would an equivalent button-rifled Schneider barrel with its residual hoop stresses resulting from the buttoning. That extra internal barrel expansion is no problem shooting lead-cored bullets, but can cause barrel obturation problems shooting non-deforming copper bullets.

All of my 375-caliber rifles are hunting rifles chambered in 375 H&H Magnum.

Jim Boatright

Jim, I know this is an old thread and I'm way off topic... I have been searching for someone who makes LAW brakes other than Pacific Tool. It seems that McPherson has retired, and as of now I have found no apprentice that he has trained. Do you have any info on where I could find these? I would love to put one on my 45/70 and another on my 300WM
 
I have not touched base with Mic McPherson since COVID-19 began. I would recommend a simple little high-evacuation-rate brake on the straight walled 45/70, no matter how hot you might load them. I used bulk packed Remington 300 grain JHP bullets at 2300 fps for plinking from Winchester high-wall and Marlin lever rifles. No MB needed.
The difficult machining of the LAW MB is installing the gradual straight inside taper: step drilling followed by step reaming. I recommend using a leaded steel alloy such as 12L14 for the LAW MB, given the amount of stock removal required. That is what mine are made from with a nice chemically applied finish.
A photo of my 338-caliber LAW brake installed on a Schneider test barrel along with some shop-made barrel tuning devices is included near the end (Page 25) of the attached paper on rifle barrel vibrations. The data used comes from QuickLOAD(c) and my own (freely available) Excel spreadsheet calculations.
 

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I have not touched base with Mic McPherson since COVID-19 began. I would recommend a simple little high-evacuation-rate brake on the straight walled 45/70, no matter how hot you might load them. I used bulk packed Remington 300 grain JHP bullets at 2300 fps for plinking from Winchester high-wall and Marlin lever rifles. No MB needed.
The difficult machining of the LAW MB is installing the gradual straight inside taper: step drilling followed by step reaming. I recommend using a leaded steel alloy such as 12L14 for the LAW MB, given the amount of stock removal required. That is what mine are made from with a nice chemically applied finish.
A photo of my 338-caliber LAW brake installed on a Schneider test barrel along with some shop-made barrel tuning devices is included near the end (Page 25) of the attached paper on rifle barrel vibrations. The data used comes from QuickLOAD(c) and my own (freely available) Excel spreadsheet calculations.

Wow, that is an extremely detailed write up! Thanks for the info, I'll need to go over that more closely when I get the chance. "Gradual straight inside taper" is a technique or profile I have never heard about. I have looked up nearly as much as I could on these brakes in the past 8 months or so and really only found pictures and brief descriptions such as "Lightweight Air Working" and "They're not just straight holes. There's a science behind it". What really intrigues me is that the people I spoke to say it almost makes their gun more quiet, or they didn't notice a difference in sound. It was my impression that muzzle brakes make guns much louder, so that seriously caught my attention. It also seems as if each one is a custom piece. No two pictures look the same. Some look like they need to be timed and others look like all the conical holes are evenly spaced. I spoke with the people over at Pacific Tool and they aren't even willing to change so much as thread pitch on the LAW brakes they make, but they do seem to have the hole shape correct. Another person who knows Mic McPherson had informed me that they are a "knockoff of his first generation LAW brake.", which also looked to not need timing. Same person is who let me know that McPherson is done gunsmithing, but he's still writing more books. It's a shame he didn't have an apprentice to teach his techniques to.


Last year I picked up a couple of the new Ruger Marlins. Went with the Trapper and SBL. Planning on taking the SBL out for a deer or elk hunt at some point, and wanted to be able to reacquire sight picture quickly, so I'll look into the high-evacuation-rate brake style you mentioned.


I know this is a long shot, but if I am able to find a gunsmith with the knowledge to make a LAW style brake, would that work well on a 300WM?
Would you have a more effective recommendation?
I'll be using that for deer, elk, pronghorn etc.



Here are all the variations I've found online, so far:

This one from Guns Magazine looks to need timing. Also looks like the holes go from cylindrical at an angle to conical at an angle.
LAW Guns Magazine.PNG







This one is from a Marlin forum and installed on a 45/70. Looks like no timing needed and only conical drilling all the way through

LAW 45-70.PNG







Mic McPherson wrote another article in Guns Magazine and gave this picture for his 7mm RSAUM that doesn't look to need timing

LAW 7mm RSAUM.PNG







You'll recognize this one of course. Looks more unique compared to the others and needs timing.

LAW 338 Lapua.PNG






And finally here is the "knockoff" that Pacific Tool makes which looks like a hybrid of the 1st and 2nd pictures. Seems to have cylindrical holes at an angle that open up into conical holes at an angle, but no timing needed
LAW Pacific.PNG
 
My 6.5 and 338-caliber LAW muzzle brakes were custom designed by Mic and me for hard-mounting Magneto-Speed chronograph sensors. The bottom groove is for clearance of the shop-made offset sensor front-mount, and the top groove is for symmetry. The top plane of the inductive sensor must be parallel mounted 0.25-inch away from the bottom edge of the rifle's bore.
Timing the MB to the barrel is quite simple, as the muzzle of the barrel seats inside the MB on a 60-degree conical shoulder. Just trim the muzzle corners at 60-degrees until barrel/MB timing is correct. This conical mechanical interface provides great mechanical strength and alignment accuracy.
Yes, the high-pressure, overbore 300 Winchester Magnum cartridge is an excellent candidate for effective use of the LAW muzzle brake.
 
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Thanks, Nik H. Here is a new paper I am writing about the importance of minimizing initial bullet yaw and yaw-rate in long-range rifle shooting. It is based on seeing the results of many runs of my (available by email) Excel spreadsheet calculating recoil induced, vertical plane muzzle motions for different possible bullet exit times (as calculated in QuickLOAD). It answers David Tubb's aeroballistics inquiry about why Left-Hand twist barrels sometimes work better than RH twist barrels depending on crosswind direction at the firing point.

EDIT (3-26-2023): Updated attached paper. Summary section expanded.
 

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Thanks, Nik H. Here is a new paper I am writing about the importance of minimizing initial bullet yaw and yaw-rate in long-range rifle shooting. It is based on seeing the results of many runs of my (available by email) Excel spreadsheet calculating recoil induced, vertical plane muzzle motions for different possible bullet exit times (as calculated in QuickLOAD). It answers David Tubb's aeroballistics inquiry about why Left-Hand twist barrels sometimes work better than RH twist barrels depending on crosswind direction at the firing point.
Thank you @Jim Boatright

I will read it