Test: Double Tap 155 gr Gold Dot vs. Speer 165 gr Gold Dot

We recently had the opportunity to test the .40 S&W Gold Dot 155 gr JHP loaded by Double Tap Ammunition, along with the .40 S&W Speer Gold Dot 165 gr JHP, as requested by an individual LE officer. These new results are contrasted with the standard .40 S&W Speer 155 gr Gold Dot we previously tested for an LE agency:

.40 S&W Speer 155 gr Gold Dot JHP; ave vel=1166 fps (S&W 4006); gel cal= 9.5cm@ 585fps
BG: pen=13.2", RD=0.64", RL=0.32", RW=155.5 gr
4LD: pen=16.0", RD=0.60", RL=0.44", RW=155.3gr

.40 S&W Double Tap 155 gr Gold Dot JHP; ave vel=1208 fps (S&W 4006); gel cal=10cm@578fps
BG: pen=15.0", RD=0.66", RL=0.39", RW=155.6gr
4LD: pen=17.1", RD=0.55", RL=0.42", RW=155.2gr

.40 S&W Speer 165 gr Gold Dot JHP; ave vel=1092 fps (S&W 4006); gel cal=10cm@578fps
BG: pen=15.0" RD=0.63", RL=0.37", RW=165.2gr
4LD: pen=16.5", RD=0.55", RL=0.51", RW=165.4gr

http://i459.photobucket.com/albums/q...g?t=1234162840
Double Tap 155gr Gold Dot & Speer 165 gr Gold Dot

Both newly tested loads performed adequately, however, there was a noticeable increase in flash, blast, and recoil with the Double Tap ammunition. Neither the Speer 165 gr Gold Dot nor the Double Tap Ammunition 155 gr loading was able to outperform the standard .40 S&W 155 gr Speer Gold Dot loading.

Thank you for this testing, Doc. I knew from my own understanding of bullet construction that increased velocity for a given bullet weight does not improve penetration and expansion. Each JHP has an expansion threshold and a .40S&W simply will not expand beyond .6x" with any reliability. The most influencial factors seem to be bullet mass and sectional density.....not velocity.

I think we can pretty much stick a fork in this one.......Double Taps loads do not "dramatically" increase performance as they claim, and their testing data is grossly inaccurate if not just outright made up. There might be "slight" improvement, but when it comes to shooting substances increasing bullet mass is superior to increasing velocity.

Double Tap data:
155gr Gold Dot JHP @ 1275fps - 13.00" / .76"

.40 S&W Speer 155 gr Gold Dot JHP; ave vel=1166 fps (S&W 4006); gel cal= 9.5cm@ 585fps
BG: pen=13.2", RD=0.64", RL=0.32", RW=155.5 gr
4 layers denim: pen=16.0", RD=0.60", RL=0.44", RW=155.3gr

.40 S&W Double Tap 155 gr Gold Dot JHP; ave vel=1208 fps (S&W 4006); gel cal=10cm@578fps
BG: pen=15.0", RD=0.66", RL=0.39", RW=155.6gr
4 layer denim: pen=17.1", RD=0.55", RL=0.42", RW=155.2gr

.40 S&W Speer 165 gr Gold Dot JHP; ave vel=1092 fps (S&W 4006); gel cal=10cm@578fps
BG: pen=15.0" RD=0.63", RL=0.37", RW=165.2gr
4 layer denim: pen=16.5", RD=0.55", RL=0.51", RW=165.4gr


I see two more inchs of bare jell penetration and one inch more penetration in denim with the DT 155.

Perhaps you are missing the point. If these numbers are indeed representative of the rest of Double Taps ammunition, then the testing data that DT has been putting out is most likely false. Doesn't that give you pause on anything they are trying to sell you? I think a pressure test of their ammunition might also be in order.

Anything DT can do, Federal, Winchester, and Speer can do better and safer given that they actually employ real engineers.

As I said earlier, increase the bullet weight(and sectional density), and the heavier loads are superior to the lighter ones.....even when they are cranked up in velocity:

.40S&W 180gr(996fps) Speer Gold Dot:
Bare Gel: 14.8”/.67”
Through Denim: 18.2”/.61”

Better recoil management, lower blast, lower flash, and it does better overall than Double Tap's supercharged 155gr load.

If additional penetration is what you want given that the average human torso is only 8" from front to back, then I guess Double Tap might be for you. However, considering that most loads that penetration 12" in ballistic gel usually exit the body in shootings, that increased penetration might be a moot point.

I get your point and generally concur. But Doc should have at least used a Glock 23 to make a proper comparison if his intent was to compare to DT data. I suspect he was just tested the load and you tried to extrapolate the data. By comparing testing using a Glock 23 and SW4006.

Glock 23 barrel length: 4.02"
S&W 4006 barrel length: 4.05"
Sig P229 barrel length: 3.94"

CCI Speer Gold Dots averages from 10-shot samples:

155gr:
-Sig P229 1180fps
-Glock 23 1192fps

165gr:
-Sig P229 1139fps
-Glock 23 1148fps

180gr:
-Sig P229 993fps
-Glock 23 998fps

If I remember correctly the Sig and the Glock have polygonal rifling that adds about 50fps in velocity.

The Smith does not have polygonal rifling.

Why did you use a Sig compared to the Glock when the actual firearm that would be a 4006.

If you did this intentionally, than you are being intentionally dishonest and attemping to mislead.

Quote:

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Originally Posted by sjc3081

Why did you use a Sig compared to the Glock when the actual firearm that would be a 4006.

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.....because Sig Sauer uses standard rifling and the comparison would be very similar to that of the S&W 4006 which also uses standard rifling. I should know, I'm a Sig armorer and have used the 4006 for duty carry in the past. Couldn't find any Glock 23 and S&W 4006 velocity comparisons because the 4006 isn't very common. Sig P229s are.

Polygonal rifling doesn't add as much velocity to a bullet as is claimed.

sjc -- I don't think a tiny change in barrel length or rifling is going to explain the difference between Doctor Roberts's independent controlled test results and the stuff Double Tap is claiming. My opinion, you are off base calling it misleading and dishonest.

The 4006 is very common in CA, as it is the standard issue CHP pistol. On the other hand, Glocks in calibers other than 9mm are not something I am fond of. FWIW, there is minimal difference in velocity between conventional and polygonal rifled pistol barrels--something around 10fps or so. Bottom line, in this test, the DT ammunition offered NO advantages over standard factory ammunition and had the disadvantage of increased flash, blast, and recoil. Pressure testing might be prudent as well.