Calculate BC with Labradar

Labrabaco is a really neat tool that takes the “ShotXXXX Track.csv” files Labradar writes to SD cards and calculates a BC (G1, G7, G8, RA4 rimfire) from the data.

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It is written entirely in javascript, and runs in your browser. There are no server-side components. There is nothing uploaded to the server. There are no cookies. I shit you not (and if you don’t believe — read the code).

My deepest gratitude goes to entoptics @ longrangehunting.com forums, who has contributed multiple high-quality datasets and data processing ideas, to design, test and fine-tune the algorithms.

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You can even save the webpage as an archive on your computer and it will work offline.

I don’t know how accurate the software is. More importantly, I don’t know how accurate the LabRadar is! I have certianly seen weird stuff happen when using it. Such as phsycially impossible “phantom” trace-tails that continue on at distances behind the target and show increased velocity. (This happens more at indoor ranges.) At the end of the day, the LabRadar is first-generation consumer-level technology. I’ve heard the company making it is the same one who makes the high-end ballistic dopplar radars companies like Hornady use to develop their bullets. I’ve heard the cost of those was into the hundreds of thousands of dollars. Here’s a neat story about Hornady using that high end gear to discover their bullet tips were melting, and prove they fixed it. You can see the fancy radar at about the 1:50 mark. It’s physically much larger than the Labradar. There’s only so much a small radar powered by AA batteries can do.

But even if the results are noisy, and amateur — there is still a lot of value in something that is easy to use, and boils down observations to a comparable number! It’s a better way of quantifying drag than “feet per second lost per yard traveled”, which is what I had been using. (Yes, I know that drag is actually a function of the square of the velocity, so that unit is fundamentally wrong. But the truth is, with the limited distance that I could observe, it was a more useful way to compare bullet performance in practice. Strange but true.)

I don’t compare the data I could get from a Labradar to the data I could get from a industrial grade systems. I compare it to having nothing — because the reality is I can’t set up better systems downrage at many ranges I shoot at. Sure, in theory I could plan a weekend around a well-prepared shooting trip. But in practice, it’s easier for me to squeeze in a quick trip to an indoor range during the week. The Labradar lets me get data from those trips, even if the environment isn’t ideal.

I guess that’s a really long winded way of saying that even if the BC numbers don’t agree with higher-accuracy measurements, and don’t work perfectly with ballistics software, they are still very useful. You can at least compare amunition you measure. And in the real world the ease of use is the the difference between having actual data, instead of gut feelings.

H4198

H4198 is a small stick-powder. Part of the “Extreme series” of powders that promise more consistent velocity at different temperatures. Old volumetric data may be obsolete, because kernels were shortened to improve metering, and new deterrent coatings added. IMR4198 is a different powder, despite the very similar name and IMR now being owned by Hodgdon powders (The “H” in H4198). They are similar powders, which in some ways is better since not every mixup will be catastrophic, but in some ways it is even more confusing.

Pictures and chemical analysis.

Bottom line: still evaluating. I have gotten good performance in 17 Ackely Hornet. It meters well for a stick powder, but with small hornet cases a fraction of a grain difference can matter.

Pros

• Meters well for a stick powder (small kernels)

Cons

• Stick powder shape does not meter as well as other shapes.
• Confusingly same name to IMR 4198 which is close but not interchangeable

Redding 3BR Pistol Insert

grains_thrown = 0.18 * pistol_insert_number – 0.33

pistol_insert_number = (grains_thrown – 0.33)/0.18

Accurate #7

“Accurate No. 7 is an intermediate burning, double-base, spherical powder … an excellent choice for high performance semi-auto handguns such as the 357 Sig, 38 Super, and 40 S&W. No. 7 is also a cost effective solution in larger magnum handgun calibers. Made in the USA.” Basically it is the slowest non-magnum pistol powder in the Accurate lineup. Similar to Longshot. It has less flash than Power Pistol, which is another excellent choice for high performance semi auto loads.

Bottom Line: Still evaluating.

Pictures and chemical analysis.

Pros:

• Throws accurate charges

Cons:

• bad feel when meetering — lots of resistance, like plastic or gum is in the mechanism

Ranier 185 Grain Flat Point (Discontinued)

I wish Ranier Ballistics would make bullets again. They had a line of plated bullets that competed with Berry’s Bullets, and they made my favorite 250 grain slug for 45 ACP. Sadly, changes in Washington state’s political climate pushed them out of business. But I did order 1500 of their 185 Grain Flat Point bullets at a great clearance price. Unlike the 250 grain slug, I really haven’t been able to get these to work well for me. They have a narrow profile that seems like it’d feed well, and and dummys seem to cycle smoothly, but I have feeding problems I don’t understand in 1911s.

The bullet OAL is 0.5240″

45 Colt: Starline, WLP primer, #80≈ 9.0-9.1 grains of VV N320, 1.5980″ OAL. 👎 bit of spitting in a 5.5″ FA M95. More muzzle flash indoors than I expected, but not overpowering. 941fps avg, ES 149=1029-880, StdDev 38.9(18x). VV Data says 8.9gr gives 1076fps in a 6” test barrel (MAX of 9.6gr 1175fps).

Interestingly, I had good success with VV N320 in 45 Colt in the same gun, but using #58≈6.6gr of VV N320, and a heavier 255gr Bear Creek RNFP for 808 fps on average, ES of 44=833-789, StdDev 11.5(15x). I don’t know how much is bullet weight, and how much is diameter.

45 Colt + True Blue

45 Colt is a wonderfully flexible cartridge in modern guns and True Blue is a particularly flexible powder that meters extremely well. I’ve been trying to standardize on using it more places.

I’ve also been trying to standardize on WLP primers, because they’re used for both +P/magnum and regular 45 Colt loads, and resist piercing. I may rethink this because of supply chain issues, and because they don’t feed as well through some primer tube fillers. But for now all of this data uses WLP.

45 Colt Loads, all using WLP primers

Bullet	Charge	Firearm	Velocity	ES	StdDev	Case	Ctg. OAL	Bul. OAL	Notes (Labradar series)
255gr RNFP Bear Creek	#45.75≈8.8gr True Blue	5.5″ Ruger Bisley	896	41=916-875	14.28(6x)	2x Starline	to cannelure,(1.5785″ approx)	0.651″	(S334, Shot record: 875, 892, 916, 905, 900, 888). Shot Indoors at 7 yards. Max for 45 Colt (14kPSI) per WesternPowdersHandloadingGuide8.0_WEB with a different 255 grain lead slug at 954 fps in a 7.26″ test barrel.
255gr RNFP Bear Creek	#45.75≈8.8gr True Blue	20″ Rossi 454	1092	23=1106-1083	12(3x)	2x Starline	to cannelure,(1.5785″ approx)	0.651″	(S392, 40 yards, same batch as S334)
255gr RNFP Bear Creek	#50≈9gr (RCBS scale) True Blue	5.5″ Freedom Arms M97	930	53=962-909	15.9(10x)	2x Starline	to cannelure,(1.5785″ approx)	0.651″	(S387, ~10-15 yards indoors)
225gr Penn Wadcutter	#50≈9gr (RCBS scale) True Blue	5.5″ Freedom Arms M97	1004	10=1009-999	3.4(5x)	2x Starline	to cannelure, 1.386″	0.5445″	(S388, ~10-15 yards indoors, loaded in same batch as S387)

Lyman #358093 a .357 spire-point (Matt’s Bullets)

While browsing Matt’s Bullets I saw a neat looking 38 caliber option: a 125 grain spire point gas checked design Lyman mold #358093, and had to order 100 to try. They were excellent quality, weighed 128.3 grains, and were 0.6855″ long.

While the bullet does look neat, and punches super clean holes in paper just like a semi-wadcutter — I do not recommend the bullet because it has feeding limitations and does not seem to be better than a more conventional design. The pointed tip means it can not work in tubular magazines. It did not feed in a Coonan semiautomatic that uses a box magazine. I just don’t see an advantage to this bullet over a more conventional SWC or round-nosed design. They look cool, but the shapes we’re used to seeing are popular for a reason.

The shape is a bit less aerodynamic at supersonic speed than it looks. at 1506fps the slug lost 6 fps/yard, while a lighter 110 grain XTP bullet, going even faster (1755fps) had less drag, losing only 5.2 fps/yard. I haven’t done a broad survey of the drag of different bullet shapes in this weight class, so perhaps I’m being unfair. But if a widely available bullet like the 110 grain XTP outperforms it — I just don’t see any reason to keep investigating this unusual mold.

Matt is kind enough to include some scanned load data from the Lyman Cast Bullet Handbook Third Edition on the page. I have the 7th printing of that book and it does not have data for the slug anymore.

Load	Coonan (5″ large-chamber semi-auto)	T/C Contender (12″)	1873 Carbine (16″)
New Sig factory-primed brass, #55.25 ≈ 8.8gr Power Pistol, seated to cannaluer	1296 avg (6 shots, ES 101=1346-1245); — S243	1506 (1 shot, pierced primer) — S242	1665 fps (1 shot) — S242
10.0 grains Blue Dot (no other details recorded, from early 2016)	1399 avg (5 shots, ES 86 = 1445 – 1359); — S45

A big shout out to Matt’s Bullets for selling these kinds of oddball designs. Sometimes you just need to try something to know if it will work. I’ve had particularly good results with the 38 caliber and 45 caliber, ultralight wadcutters. They’re just fun. Even though this particular slug wasn’t a success for me — I learned something.

Marlin 1894 357 Magnum 20″ Carbine with JM Stamp and Microgroove Barrel

Unfortunately the microgroove limitations with cast bullets seem to be real. I’ve noticed worse accuracy with some lead slugs. However I haven’t had enough time with this rifle yet to be absolutely sure.

357 Magnum loads in a 20 “Microgrove” JM Marlin carbine

Bullet	Charge	Velocity	ES	StdDev	Case	Primer	Ctg. OAL	Bul. OAL	Notes (Labradar series)
110gr Hornady XTP	#59≈6.5-6.7 VV N310	1514	35 = 1536 – 1500	15.46(6x)	Mixed	Win WSPM	1.58	0.4925″	(S395). 7 yards. 1213 1x in 5″ Coonan. Load data is START from VihtaVuori, predicted 1355fps in a 7″ test barrel. N310 is a very fast powder. The report did sound different but was still loud. 👎 I can’t really recommend this load – such a fast powder makes me nervous, and the results weren’t special enough.
105 Grain TCFP (coated) Cowboy #16	1.3cc LEE dipper ≈ 5.5gr Trail Boss	1293			Mixed	Win WSPM	OAL	0.528+/- per mfg. I measured 0.5315.	(S398). Very quiet, so only one registered. Low Recoil. I suspect this may not be very accurate but need to benchrest it. 1050 fps in Coonan (S399), would reliably cock hammer but never eject.
Sierra 125gr JSP	#62.5≈9.4 – 9.6 Longshot	1763	68 = 1798-1729	19.83 (9x)	Mixed?	Win WSPM	1.5825 (Need to double check)	0.5280-0.5295	(S397). (S396 is the same batch in Coonan 5″ 1911, 1323 avg of 5 shots, 113 ES, 52 StdDev. Very loud in that gun.)
155grain LSWC Lyman #358477. from Matt’s Bullets	#38≈4.6gr Bullseye	1161			Starline, Nickel, new	CCI 500	Need to measure OAL	0.6665	(S400). Crimped in the cannelure. ~.359″ diameter. Consistent (1176,1157,1157,1153). Mild report. 1100fps in 12″ T/C barrel. Cycled OK and seemed accurate, but I didn’t benchrest.
180 grain RNFP “.357 Striker” from Missouri Bullet Company (uncoated)	#36.5 ≈ 5.6 to 5.7 grains Longshot	1164	27 = 1180 – 1153	10.49(7x)	Starline, nickel plated 1x fired	Win SPM	1.585″	0.7575 measured (.761 nominal)	S402. 24 yards. 👎 Not accurate for me. Fed well. Primers looked OK. About ~900 fps in Coonan (S401), stovepipe malfunction. 1219 (only shot one) in 16″ 1873 carbine barrel, different batch and CCI SP primers but same charge
Hornady 180 grain XTP	#70≈10.8-10.9gr VV N110	1325	59	24.3 (5x)	Starline (new)	WSPM	1.585″	0.7535″	(S437). 25 yards Indoors.
Hornady 180 grain XTP	#75≈11.6gr VV N110	1439	70	26.9 (5x)	Starline (new)	WSPM	1.585″	0.7535″	(S438). Primer cratering 25 yards Indoors. Same lot as S437 above, fired same time, only varied charge weight. Data safe per Hornady 10 and Lyman.

Vihtavuori N110

Vihtavuori N110 (aka 4N19 and N3SS) is a tubular power with small (1.1mm long, 0.8mm diameter) granules. It is the fastest burning powder in the VV rifle powder line. “The ignition is best with small rifle primers, and it’s suitable especially for small rifle cases like .22 Hornet, .30 Carbine, but also Magnum pistol and revolver cartridges.” I believe the name was chosen to match H110, but I do not know for sure.

Pictures and chemical analysis sample.

Bottom line: 👍 so far, but still evaluating

Pros:

• Meters OK
• Very low flash
• Should take to downloading better than H110
• Versatile for a magnum powder, have successfully used in 38 Special

Cons:

• Meters less smoothly than H110 in a powder throw
• Generally more expensive than most pistol powders (but remember: powder is generally the least expensive part of a pistol round)

VMD of .08330 (cc/grains)

Redding 3BR Pistol Insert

MAX throw at #99 is 15.4 grains

grains_thrown = 0.1515 * pistol_insert_number + 0.3253

pistol_insert_number = (grains_thrown – 0.3253)/0.1515

Vihtavuori N320

Vihtavuori N320 (previously called 3N22) is fast single-base porus tubular handgun powder with small grains (1.1mm x 0.8mm) and a decoppering agent. Pictures and chemical analysis sample 1, sample 2

Bottom line: Still evaluating.

Pros:

• Meters well.
• Double charge is easy to see.

Cons:

• Generally more expensive than most pistol powders (but remember: powder is generally the least expensive part of a pistol round)

VMD of .1210 (cc/grains)

Throw accuracy ≈ 0.1 grain

Redding 3BR Pistol Insert

grains_thrown ≈ 0.1074 * pistol_insert_number + .39

pistol_insert_number ≈ (grains_thrown – .39)/0.1074

Vihtavuori N310

Vihtavuori N310 is a very fast burning powder for light handgun loads. “Vihtavuori N310, known as N14 back in the old days, is a single-base, tubular powder type with grain dimensions of 0,7 mm length and 0,6 mm diameter. …The N310 is also used by many blank ammunition manufacturers.”

Bottom line: 👎 so far because it just hasn’t performed better than other faster powders and is more expensive, but still evaluating.

Pros:

• Meters well.
• One of the fastest burning powders avalible, stick shape should be easier to ignite.

Cons:

• Generally more expensive than most pistol powders (but remember: powder is generally the least expensive part of a pistol round)

VMD of .1214 (cc/grains)

Throw accuracy ≈ 0.1 grain

Redding 3BR Pistol Insert

grains_thrown = 0.1095 * pistol_insert_number + 0.1613

pistol_insert_number = (grains_wanted – 0.1613)/0.1095