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Tiberius 9.1 Barrel/FSR Consistency Test


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#1 UV Halo

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Posted 02 October 2011 - 03:45 PM

I started shooting First Strike Rounds with the T9.0, and the LAPCO .690 barrel. Once I got it tuned and feeding properly, It was an excellent performer, with a very high consistency (perceived +/- 1FPS) , and I dubbed it "Totmacher". I only upgraded to the 9.1 for the new ASA, and ultimately the Rifled Barrel.

With the 9.1, I instantly upgraded to the Rifled Barrel (LAPCO manufactured, Tiberius Sold) and I faced some serious issues. The first major problems I faced were Barrel Jams and Velocity Consistency. I sent the gun into Tiberius Arms for them to check out. The found that the o-ring (factory supplied) between the body and the ASA was of the wrong durometer (hardness), resulting in it getting squished and restricting the air path. They returned the gun to me, and I still had problems but, they were slightly reduced. I later found the barrel jam problem to be the result of heavy use (100+ shots) between barrel cleanings. Once I got past that, I dubbed it "Totmacher 9.1SD" and I started using the marker regularly (to include LL4).

However, one problem always remained- Velocity consistency. This gun has never felt to be anywhere near the consistency of my 9.0. I've had the suspicion for awhile now that the cause of the inconsistency was the gun's reg. The T9x regs are 'un-balanced' meaning that a rise in the input pressure will result in a rise in the output pressure. When it comes to unbalanced regs, better regs have a better ratio. For example, Palmer's regs are claimed to have a 72:1 (input:output) ratio so, it would take a 72 PSI change on the input to register a 1 PSI change on the output. Regs also often have an optimal adjustment range (# of turns) and if you adjust outside of this range (i.e. all the way in, or out), you begin to see output inconsistency.

When you switch to the Rifled Barrel, you have to increase the output of the reg usually by two or more full turns, to get your velocity back up. I suspect that this adjustment puts the reg out of it's optimal adjustment range, leading to a decrease in consistency. To confirm this, I also tested a Ninja 45ci tank with an SHP reg. The higher input pressure to the gun means I don't need to have the gun's reg turned as high so, it should be closer to it's optimal adjustment range.

That's all the theory behind the test, now let's get down to it. The test setup:

Tiberius T9.1 with
  • Polished "firing pin/bolt"
  • Ported ASA/Body oring (increased flow between ASA and body)
Air Systems Used
  • Ninja 45ci (standard- 850PSI)
  • Ninja 45ci SHP (~1100PSI)
Barrels Tested (each was cleaned prior to each test)
  • LAPCO STR8Shot First Strike Ready T8.1/T9.1 - 16" .690
  • Tiberius Arms (LAPCO) 9.1 FSR 14" Rifled Barrel - 0.683
Chrono used: Custom Chrono Inc. X-Radar

My Lovely Assistant (Girlfriend) and I would chrono the gun into the 270s and then, I'd fire a shot, she'd write down the FPS for a 20 shot string. We did this all within the span of an hour (10-11 am) and there no significant changes in the weather. We shot the following configurations:
  • T9.1 with .690 Barrel and Ninja 45ci (standard)
  • T9.1 with Rifled .683 Barrel and Ninja 45ci
  • T9.1 with Rifled .683 Barrel and Ninja 45ci SHP
The Data

My Findings:
  • T9.1 with .690 Barrel and Ninja 45ci (standard) FPS Standard Deviation: 4.68
  • T9.1 with Rifled .683 Barrel and Ninja 45ci FPS Standard Deviation:12.72
  • T9.1 with Rifled .683 Barrel and Ninja 45ci SHP FPS Standard Deviation: 8.36
In these numbers, The Standard Deviation represents how consistent the configuration is. For example, the T9.1 with the .690 LAPCO barrel, could be stated as being +/- 4.68 FPS for 68% of the times it was shot. Therefore a lower number is better.

The gun is clearly less consistent when using the rifled barrel. The decrease in the rifled barrel's SD while using the higher output SHP seems to indicate that the problem does in fact exist in the gun's regulator. Further testing with an even higher output tank reg would confirm this.

Now, maybe those numbers don't quite speak to you. Well, let's see what these SD's mean in regards to trajectories:

In the following graphs, The blue line indicates the perfect 280 FPS trajectory. The red line shows the upper edge of where 68% of your shots will fall while the Grey line shows lower edge. Keep in mind that this is only the 'majority' of your shots. To get a rough idea of where all of your shots will spread to, double the widths of the tracks. These tracks continue to get wider, at the same rate all the way out to the maximum range.

T9.1 with .690 Barrel and Ninja 45ci (standard)
Posted Image


T9.1 with Rifled .683 Barrel and Ninja 45ci
Posted Image

T9.1 with Rifled .683 Barrel and Ninja 45ci SHP

Posted Image

So, with the rifled barrel, and my regular output Ninja tank, firing at a target 50yds away, I could see my first shot fall 10" low, and then I compensate by aiming 10" higher, only to have my shot go over the target by 20". In real world situations, I have had this happen.

Comments, Questions?

Edits: Fixed Links, and spelling

Edited by UV Halo, 27 November 2011 - 07:28 PM.


#2 andrewthewookie

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Posted 02 October 2011 - 03:52 PM

Were you able to notice whether or not the rifled barrel improved on the accuracy of the FS rounds, or did the inconsistency keep any improvements over the smooth barrel from happening?

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#3 UV Halo

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Posted 02 October 2011 - 03:55 PM

Were you able to notice whether or not the rifled barrel improved on the accuracy of the FS rounds, or did the inconsistency keep any improvements over the smooth barrel from happening?


This wasn't an accuracy test as in my opinion, you need to nail down consistency first. However, my experience leads me to believe that they spread less (left/right) than when fired out of a smoothbore.

#4 rntlee

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Posted 02 October 2011 - 06:02 PM

I've not heard great thing about the Lapco FS rifled barrel. I've read that the rounds occasionally come out damaged. This would lead me to believe that the inconsistency you notice originates in an interference fit between rounds and barrel.

#5 UV Halo

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Posted 02 October 2011 - 07:45 PM

I've not heard great thing about the Lapco FS rifled barrel. I've read that the rounds occasionally come out damaged. This would lead me to believe that the inconsistency you notice originates in an interference fit between rounds and barrel.


Actually, I rarely have had that problem (no more so than with my .690 smoothbore) once I started cleaning the barrels after every 50ish rounds. When it does happen, I can't attribute it to the barrel since I don't routinely inspect the rounds before loading them (to look for hairline cracks in the fins).

#6 baccummba

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Posted 26 November 2011 - 07:53 AM

I am running the FSR Rifled barrel and T9.1 setup and have first hand experienced these inconsistencies and quite franky its bugs the shit out of me. Do you think the .686 barrel would perform more consistently? What air setup would you recommend? I have a 13cu 3000psi tank and am debating getting a ninja reg for it, would this increase consistency you think?

#7 MrEeske

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Posted 26 November 2011 - 05:38 PM

How does the rifled profile of the barrel compare to the fins of the rounds?

(1) Rifling direction (clockwise versus counter-clockwise)
(2) Number of grooves in barrel bore versus number of fins on round
(3) Aggressiveness of rifling twist (i.e., is the angle of twist greater, equal to, or less than the angle of the round fins)

Nice experiment writeup.

I'm confused on how to read the graphs; however, they are pretty. Do the graphs imply that all shots impacted the ground 50 yards out, or are you just extrapolating out the data past the point of impact?

Also, I don't understand what you mean by "0.280 FPS trajectory"; are you saying that you had the gun angled so that the rounds would exit the barrel with a climb rate of 0.280 ft/s?

Moar experimentation! Posted Image

[Edit] Shucks. I just realized this thread is almost 2 months old. Posted Image [/Edit]

Edited by MrEeske, 26 November 2011 - 05:42 PM.


#8 UV Halo

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Posted 27 November 2011 - 07:53 PM

I am running the FSR Rifled barrel and T9.1 setup and have first hand experienced these inconsistencies and quite franky its bugs the shit out of me. Do you think the .686 barrel would perform more consistently? What air setup would you recommend? I have a 13cu 3000psi tank and am debating getting a ninja reg for it, would this increase consistency you think?


The .686 is intended for those who shoot regular paint and FS rounds in the same game. LAPCO and I recommend the .690 for those who are just shooting FS rounds. I also recommend the ninja reg as they have performed excellently in my setups and, they performed the best in punkworks testing.

How does the rifled profile of the barrel compare to the fins of the rounds?

(1) Rifling direction (clockwise versus counter-clockwise) Counter-Clockwise
(2) Number of grooves in barrel bore versus number of fins on round 14 Grooves, 16 Fins
(3) Aggressiveness of rifling twist (i.e., is the angle of twist greater, equal to, or less than the angle of the round fins)Equal


Replies in Blue.

Nice experiment writeup.

I'm confused on how to read the graphs; however, they are pretty. Do the graphs imply that all shots impacted the ground 50 yards out, or are you just extrapolating out the data past the point of impact?

Also, I don't understand what you mean by "0.280 FPS trajectory"; are you saying that you had the gun angled so that the rounds would exit the barrel with a climb rate of 0.280 ft/s?

Moar experimentation! Posted Image

[Edit] Shucks. I just realized this thread is almost 2 months old. Posted Image [/Edit]


Thanks. Okay, so, I had a typo early on that should have read "the perfect 280FPS trajectory". It's fixed now.

The graphs are based on the ballistic performance of First Strike rounds (see my External Ballistics Primer in my sig if you want to know how they are generated). What they show is how much the rounds drop, in inches over yards flown. For example, a round fired at 280FPS will drop 10 inches by the time it flies 20 yards. The blue curves represent a perfect 280FPS shot. The red curves represent FPS deviations above 280, and the gray curves represent FPS deviations below 280. Combined, each pair of curves describe the vertical spread you are likely to experience when using the combo (air system, barrel) that each graph applies to.

Honestly, I think that in this sub-forum, reading a bit, and asking a question is of more value than simply asking a question for something that has already been answered/covered.

#9 MrEeske

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Posted 27 November 2011 - 11:31 PM

Honestly, I think that in this sub-forum, reading a bit, and asking a question is of more value than simply asking a question for something that has already been answered/covered.


My apologies for giving you the benefit of the doubt that the graphs directly reflected physical measurement. You didn't state how you crafted the numbers that the graphs reflect; how was I, or anyone else, supposed to know to click through the several links in your signature to get an answer?

I think my confusion stems from why you're parading around drop over distance data points, when the point of the experiment was "velocity consistency."

From what I'm understanding, you didn't actually measure any distance and the numbers are just guesses generated by a mathematic model; correct? If that's so, how do you know that the aerodynamic fins don't impart some kind of force that isn't taken into account by the model? In summary: how well do your modeled numbers line up with what actually happened in front of you? Since this is an old thread that I unintentionally helped dig up, that's more of a question for future experiments.

Edited by MrEeske, 28 November 2011 - 12:01 AM.


#10 UV Halo

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Posted 27 November 2011 - 11:58 PM

Honestly, I think that in this sub-forum, reading a bit, and asking a question is of more value than simply asking a question for something that has already been answered/covered.


My apologies for giving you the benefit of the doubt that the graphs directly reflected physical measurement. You didn't state how you crafted the numbers that the graphs reflect; how was I supposed to know to click through the several links in your signature?

From what I'm understanding, you didn't actually measure any distance and you're just guessing at the distances through a mathematic model; correct? If that's so, how do you know that the aerodynamic fins don't impart some kind of force that isn't taken into account by the model? In summary: how well do your numbers line up with what actually happened in front of you? Since this is an old thread that I unintentionally helped dig up, that's more of a question for future experiments.


No worries. My apologies for not highlighting my ballistics research. Just to be clear, I personally prefer it when someone resurrects a thread to clarify their own understanding of the content, rather than opening an entirely new thread asking the same initial question.

I'm not merely guessing. I'm conducting calculations based on data that has been physically collected. Bryce and Cockerpunk collected dual chrono data for the FS rounds. This data allowed me to determine the Ballistic Coefficient, that when combined with the known weight for the FS rounds, allowed me to calculate the trajectories for them. I'm not trying to brag here but my calculations have shown themselves to be very accurate when compared to real-world performance. With the First Strike rounds in particular, three weeks before TechPB Mike did his on camera range testing of First Strike rounds, I predicted (on the forums, in this thread) that First Strikes would fly a maximum of 519ft. On camera, Mike hit Willie on the shoulder at 517ft and at that end of the trajectory, the rounds are traveling mostly downward.

There's only one question remaining in the performance of First Strike rounds- The rifled barrel. Presently, nobody has conducted/shared dual chrono data for the rounds exiting a rifled barrel. For my calculations this may have an impact. If the barrel is pre-spinning the rounds to the correct RPM, then it should go to follow that the rounds will experience a slight reduction in drag once, they leave the barrel. For these charts, the exact numbers for the T9.1/Rifled Barrel/Ninja SHP reg could change but, the spread wouldn't.

#11 MrEeske

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Posted 28 November 2011 - 01:58 AM

I predicted (on the forums, in this thread) that First Strikes would fly a maximum of 519ft. On camera, Mike hit Willie on the shoulder at 517ft and at that end of the trajectory, the rounds are traveling mostly downward.

Your point and case. I don't think I'll be so quick to question the accuracy of your models in the future. Posted Image

I guess all of my thoughts are coming from being stunned at how neatly the First Strike rounds settle into a "generic" ballistics model formula. I was expecting something more exceptional of the First Strike rounds, like how rounds with high backspin induce lift (e.g. Flatline and Apex barrels).

I feel so behind the learning curve now...

There's only one question remaining in the performance of First Strike rounds- The rifled barrel.

A good candidate for high-speed camera footage, too; something comparable to this (of which I'm assuming the barrel is smooth bore).

Edited by MrEeske, 28 November 2011 - 02:04 AM.


#12 UV Halo

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Posted 28 November 2011 - 11:46 AM

I guess all of my thoughts are coming from being stunned at how neatly the First Strike rounds settle into a "generic" ballistics model formula. I was expecting something more exceptional of the First Strike rounds, like how rounds with high backspin induce lift (e.g. Flatline and Apex barrels).

I feel so behind the learning curve now...

There's only one question remaining in the performance of First Strike rounds- The rifled barrel.

A good candidate for high-speed camera footage, too; something comparable to this (of which I'm assuming the barrel is smooth bore).


Don't feel bad about not knowing all there is to know about paintball ballistics. :) I've been playing for over 20yrs and, it took me months of personal research just to get to the point where I could use the data Bryce and Cockerpunk collected. While I was doing my own research, I was in awe of Gary Dyrkacz. He actually attempted to predict regular paintball trajectories by using Fluid Dynamics and Newtonian Physics. In light of the data that has been collected to date, his methods turned out to be pretty accurate. My methods are only better because they are simpler, and, the real-world performance data.

The FS rounds are inherently simple since the spin is primarily intended just to keep the round pointed nose-forward. Backspinning paintballs on the other hand are inherently more complex due to the varying orientations of the seams (and their size), lopsided overall shape, and high RPMs which may or may not be consistent from shot to shot.

I wouldn't concern myself with the high speed footage of FSRs (although it would look cool). A dual chrono measurement would give me everything I need to determine if a the rifled barrel actually makes a difference in the trajactory. A rigorous accuracy test would tell me if the rifled barrel improves accuracy.

#13 supertux1

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Posted 30 May 2012 - 10:38 PM

It's great to see someone testing this. It's fairly clear that the manufacturers' don't do this kind of testing.

Not to criticize, but I see you use a doppler chronograph for your testing and a very small sample size...

Most of those doppler radio chronographs have about +/- %2 accuracy, whereas the light based ones seen in PunkWorks testing are typically +/- .5% accuracy.
Find out what yours is, if you can. The rest of this post and calculations are going to assume it's +/- %2.

Given the %2 accuracy fluctuations of radar, a minimum possible SD for radar chronograph testing @ 280 FPS, should be something like 3.21 FPS given perfect other variables and large sample with a normal distribution.
(I wrote a program to simulate 2000 shots @ 280 FPS over a chrono with +/- 2% random measuring accuracy and 3.21 FPS is the number I got for SD with Excel's STDEV() function.)

Now I haven't seen your data, but it seems like most of your results from the .690 barrel test and the rifled barrel w/SHP test fall within 1.5 to 2.5 standard deviations of what can be expected from a %2 radar chrono.
Since you only have 20 samples in each test, you could have gotten 'lucky' with one test and achieved a nice low SD and 'unlucky' with the other.

Now, that 12.72 FPS standard deviation is about four times the estimated minimum SD for radar chrono and very unlikely (1 in 15,000 chance) that the radar chrono had anything to do with those results.

Of course, this says nothing of accuracy, trajectory and final position, only consistency, so I think more consistency and accuracy tests with the .690 barrel and rifled barrels w/SHP should be conducted before a conclusion is made.
(A chrono doesn't care if your barrel rips the paintball in half, and an X-Y graph doesn't care if your shot landed on the bullseye via corkscrew around Jupiter.)

Again, it's too bad Tiberius didn't figure out that that small bore barrel would push their regulator out of the best consistency range.
Perhaps the .688 rifled hammerhead barrel would be 'better' than the .683, but not better than the smooth bore .690?

Edited by supertux1, 30 May 2012 - 10:41 PM.


#14 UV Halo

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Posted 31 May 2012 - 09:34 AM

It's great to see someone testing this. It's fairly clear that the manufacturers' don't do this kind of testing.

Not to criticize, but I see you use a doppler chronograph for your testing and a very small sample size...

Most of those doppler radio chronographs have about +/- %2 accuracy, whereas the light based ones seen in PunkWorks testing are typically +/- .5% accuracy.
Find out what yours is, if you can. The rest of this post and calculations are going to assume it's +/- %2.

Given the %2 accuracy fluctuations of radar, a minimum possible SD for radar chronograph testing @ 280 FPS, should be something like 3.21 FPS given perfect other variables and large sample with a normal distribution.
(I wrote a program to simulate 2000 shots @ 280 FPS over a chrono with +/- 2% random measuring accuracy and 3.21 FPS is the number I got for SD with Excel's STDEV() function.)

Now I haven't seen your data, but it seems like most of your results from the .690 barrel test and the rifled barrel w/SHP test fall within 1.5 to 2.5 standard deviations of what can be expected from a %2 radar chrono.
Since you only have 20 samples in each test, you could have gotten 'lucky' with one test and achieved a nice low SD and 'unlucky' with the other.

Now, that 12.72 FPS standard deviation is about four times the estimated minimum SD for radar chrono and very unlikely (1 in 15,000 chance) that the radar chrono had anything to do with those results.

Of course, this says nothing of accuracy, trajectory and final position, only consistency, so I think more consistency and accuracy tests with the .690 barrel and rifled barrels w/SHP should be conducted before a conclusion is made.
(A chrono doesn't care if your barrel rips the paintball in half, and an X-Y graph doesn't care if your shot landed on the bullseye via corkscrew around Jupiter.)

Again, it's too bad Tiberius didn't figure out that that small bore barrel would push their regulator out of the best consistency range.
Perhaps the .688 rifled hammerhead barrel would be 'better' than the .683, but not better than the smooth bore .690?


Thanks for the feedback!!

I agree, an optical would be best but, I haven't been able to convince myself to get one since I rarely, do this type of testing.

I've looked into the accuracy of Xradar products a long time ago and, if I remember correctly, they are the same folks who make the classic 'big red' and the accuracy standard is the same or not far from the 2% you mentioned. I'm now using a Virtue clock (not saying it's better, just different). One problem I have with many of the radar chrono's is no visible/audible feedback for when the device measured (vice just leaving the numbers up from the previous shot). I like the Virtue for this reason since it beeps after every shot registered. I hoped that I could use it's recording and calculations in future testing but, it only capture's a string with ROFs above 1BPS. So, the audio feedback is still helpful.

I've repeated the test of the T9.1 with .690 Barrel and Ninja 45ci (standard) and my SD came out to 4.99. Punkworks Chrono Data (optical) with the T9.0 and the stock barrel came out to 4.25. So, I'm very confident in my 'baseline' data for the smoothbore.

I've not fully endorsed the SHP tank as a solution. The best solution would be for Tiberius to re-spring their reg to get it in the correct output range for the rifled barrel. However, as they have put it to me- their engineers are too busy.

In regards to Accuracy. I'm not saying the rifled barrel is definitively more (or less) accurate overall than the smoothbore. I suspect it might be but, I do not have the ability to test the accuracy indoors (necessary for lightweight projectiles like these). What I am saying however is that velocity consistency of the rifled barrel, while using a standard output tank will negatively impact accuracy in the vertical axis, and I have experienced this impact under semi-controlled conditions (Top Paintball Sniper Competition).

I too would like to see more testing. Bryce and Gordon, plan on doing a multi-barrel T9.1 accuracy and I'm hoping, a dual chrono test (this will help me answer the question of whether the rifling reduces drag).

The challenge of the rifled barrel is to grip the round tight enough to induce a spin. It's presently unknown if the LAPCO/Tiberius Rifled Barrel actually imparts a spin.

Honestly, For this and several other reasons, I've given up on Tiberius Arms markers. I'm only using mine until something better comes along.

#15 supertux1

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Posted 31 May 2012 - 02:34 PM

Thanks for the feedback!!

I agree, an optical would be best but, I haven't been able to convince myself to get one since I rarely, do this type of testing.

I've looked into the accuracy of Xradar products a long time ago and, if I remember correctly, they are the same folks who make the classic 'big red' and the accuracy standard is the same or not far from the 2% you mentioned. I'm now using a Virtue clock (not saying it's better, just different). One problem I have with many of the radar chrono's is no visible/audible feedback for when the device measured (vice just leaving the numbers up from the previous shot). I like the Virtue for this reason since it beeps after every shot registered. I hoped that I could use it's recording and calculations in future testing but, it only capture's a string with ROFs above 1BPS. So, the audio feedback is still helpful.

I've repeated the test of the T9.1 with .690 Barrel and Ninja 45ci (standard) and my SD came out to 4.99. Punkworks Chrono Data (optical) with the T9.0 and the stock barrel came out to 4.25. So, I'm very confident in my 'baseline' data for the smoothbore.

I've not fully endorsed the SHP tank as a solution. The best solution would be for Tiberius to re-spring their reg to get it in the correct output range for the rifled barrel. However, as they have put it to me- their engineers are too busy.

In regards to Accuracy. I'm not saying the rifled barrel is definitively more (or less) accurate overall than the smoothbore. I suspect it might be but, I do not have the ability to test the accuracy indoors (necessary for lightweight projectiles like these). What I am saying however is that velocity consistency of the rifled barrel, while using a standard output tank will negatively impact accuracy in the vertical axis, and I have experienced this impact under semi-controlled conditions (Top Paintball Sniper Competition).

I too would like to see more testing. Bryce and Gordon, plan on doing a multi-barrel T9.1 accuracy and I'm hoping, a dual chrono test (this will help me answer the question of whether the rifling reduces drag).

The challenge of the rifled barrel is to grip the round tight enough to induce a spin. It's presently unknown if the LAPCO/Tiberius Rifled Barrel actually imparts a spin.

Honestly, For this and several other reasons, I've given up on Tiberius Arms markers. I'm only using mine until something better comes along.



I've been a little bored with the 'speedball / accuracy by volume' aspect of the game and want to explore new ways of playing, so I bought a basic 9.1 rifle at LL5 and fired about 100 FS rounds over half a day there. I knew nothing of this projectile's ballistic properties firsthand, how to zero the sight etc... so it was largely a guessing game, but I did manage to hit a few people and found it an enjoyable way of playing a big game. A few groups of guys called me over to hit people that were out of range for them and it was fun.

Since then I've learned a lot about how these rounds work, how they compare to other projectiles though Hawke ChairGun Pro and your BC number for FS rounds, and various anecdotes provided via forum posts and Youtube videos.

Back to the rifling, it is interesting that the 'Minie Ball', used in Civil War era rifles is similar in shape, size and function to FS rounds.

The Minie Ball has a skirt and a hollow area it similar to a FS round, with horizontal grooves that are oiled to prevent excessive drag.

With the Minie, the bullet is smaller than the bore of the barrel to allow it to be easily muzzle loaded without jamming on the rifling or debris.
The skirt is designed to expand under firing pressure and engage the rifling in the barrel, but otherwise the projectile slides by without friction.

I wonder if this is how the FS rounds could work in rifled barrels, instead of just matching the bore to the paint size.

Perhaps adding a relief cut to skirt with a razor to allow it to flex more and then using a rifled barrel that is slightly larger than .683 will achieve the intended effect without slowing the round down too dramatically.




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