Honestly. In my experience. Bullets tumble less in clear gel. But that’s my experienceOriginally Posted by JCN
Honestly. In my experience. Bullets tumble less in clear gel. But that’s my experience
Just ballpark estimations.
I don’t think anyone believes clear gel will exactly replicate organic across a spectrum of velocities and projectiles.
But is there a window of function that might be reasonable for handguns besides the standard sold “10%.”
I’m trying to get the HST to center around 13” or so. I was around 15” so still a little tweaking needed.
AmmoQuest organic gel with same model of gun and cartridge.
Mine still went too far.
AmmoQuest expansion (not sure how he is measuring)
My expansion:
Adding more 20% and seeing if I can bring the penetration down a little more.
So. You are seeing if you can duplicate a medium to a known.
That’s interesting. And probably more intensive and expensive than going with a known quantity.
Yes, with the thought that if I adjust to 950 fps HST instead of to a 590 fps BB then maybe other handgun cartridges would show reasonable similarity.
For the second part:
Maybe? Maybe not?
So far it’s cost me $5 because I have the blocks already.
The cost was in heating and ammo.
It’s just the up front time to see if it’s even possible.
But then I can explore what that looks like.
I could shoot a BB and see what distance it goes to. What if the scale on the lower end means the BB should only go 1.8” in order to get handguns to perform similarly to organic.
Especially given the non-linear comparison, it makes sense to standardize against the gold performance standard rather than the typical standardization standard…
Basically once we figure out if it’s possible then we could ask the company to make that mix.
@camel
@the Schwartz
I like the graph that Schwartz posted.
But empirically the 20% line doesn’t hold at higher velocities as evidenced by my handgun testing.
The 20% doesn’t allow more penetration than 10% organic at any velocity.
And if you notice they didn’t test the 20 at higher velocities and they were just shooting BBs.
If you took their black line at face value, that would mean at typical handgun velocities the 20% would overpenetrate compared to organic and I can assure you that does not happen in real life.
I think a more plausible explanation is that there is an oobleck type phenomenon at higher velocities with the 20% that they didn’t test.
Something like the green curve I drew.
One thing about physics modeling is that it’s often over simplified and has to be corrected with real world data when it’s really not that simple.
So basically instead of intersecting properties at 590, I’m looking to intersect curves at ~1000fps.
First step is to prove it can be done.
I added a fair amount of extra 20% so I expect the next set to penetrate under 13” but who knows.
Should be able to test it tomorrow.
Not asking this to be a dickhead: Do you know why they use steel BB's to calibrate ord gel for valid scientific testing?
I am not sure, but I love learning especially if it’s esoteric.
I would imagine a spherical projectile would be most reproducible?
I don’t know why 590 fps, maybe because that’s a typical air rifle velocity?
What I’m testing doesn’t invalidate anything done for the preparation and calibration of ORGANIC GEL.
What I’m saying and please listen to this part:
The typical organic calibration IS NOT VALID IN CLEAR GEL because of density differences and molecular differences.
So basically since the properties of the material are so different, it is not helpful to try and use the same calibration protocol.
Again, I’m not saying the calibration protocol for organic gel isn’t important. It is, especially with the heat unstable nature of organic gel.
But the 590 fps BB has been shown to not correlate with anything meaningful in a medium with different properties (see graph above).
EDIT: I wouldn’t be surprised if there had to be different velocity / penetration standards for the BB in order to get comparable handgun performance.
Like 700 fps for the BB in synthetic gel to have similar penetration to the organic distance. (3-3.7 inches) or if married to 590, then the clear gel calibration distance would have to be 1.8 inches or something similarly lower because the slope of the curve is different in order to intersect where it really matters (1000 fps).
Probably a different calibration yet for rifles and higher velocity projectiles.
Last edited by JCN; 11-27-2022 at 08:41 PM.
It is used because it (the BB) is spherical. If it ''tumbles'', uniformity is ensured because the sphere is symmetric on all axes (x, y, z).
The process is used to ensure that the gelatin has the correct viscosity so that it will represent the viscous drag component that dominates projectile deceleration in the non-cavitation velocity regime which is less than 750 fps for a BB.
Last edited by the Schwartz; 11-27-2022 at 08:42 PM.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Maybe I need to buy a 1000 fps air rifle (seriously).
Because that would be the cleanest way to compare apples to apples.
Shoot 1000 fps into organic gel and adjust synthetic gel composition to match the distance range.
That’s the cleanest comparison.
590 fps probably won’t cut it because of the different properties.
So the cross comparison likely has to be done at handgun velocities if comparing handguns.
For now, the best I have is what I have.
Data is dirtier and not suitable for scientific measurement, but it’s a proof of concept for entertainment purposes kind of endeavor.
Ah. So no 1000fps BB then. Makes sense. You just saved me some money.
What do I hope to learn?
I think at a minimum, if I can get an HST to go under 13” it’ll show that the published curve line of 20% gel isn’t accurate at higher velocities and that overpenetration isn’t a given in synthetic gel.
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