Speer Gold Dot 62gr and 75gr.

[shoobe01]

Yeah, it did.

To mount the scope (Seekins bases) I had to remove the top handguard and the backup rear sight.

Needed the stock to be longer than I could possibly get it, so the first several groups were very interesting...

I have been thinking I want to find out how accurate my carbines are (3x + RDS is hard to really tell at 300!), but have no (good) spare scope, so... I have a vague thought that when I send my precision rifle off to GAP to get the barrel cut sometime here, I'll borrow the 4-16 Steiner it wears (a huge scope for the mag) and stick it on things like my 12.5" 5.56 for range day validation. Should look very, very dumb if I execute this idea, but will get useful data on how the gun really shoots.

I'll definitely do it as semi-serious research if so, and shoot everything I have, get a couple boxes of other ammo to see what each gun likes best after all. I kinda liked that exploration for the bolt rifle (WAY too lazy and not good at that to reload these days) so may enjoy this nerding out on ammo choices for the carbines.

 

[Yondering]

Big scopes on short rifles are something that always seemed out of place to me until about a year ago when I started stretching the legs of a 12.5" SBR I built. It's not a huge scope, but I've been using a 3-9x Leupold on this little SBR, and was surprised to find it as easy to hit with at long range as the bigger guns, but still very comfortable at indoors distances. In fact, just last weekend a friend and I were making very consistent hits at 580 yards across a canyon, with this little SBR that fits in a backpack.

 

[MojoNixon]

Big scopes on short rifles are something that always seemed out of place to me until about a year ago when I started stretching the legs of a 12.5" SBR I built. It's not a huge scope, but I've been using a 3-9x Leupold on this little SBR, and was surprised to find it as easy to hit with at long range as the bigger guns, but still very comfortable at indoors distances. In fact, just last weekend a friend and I were making very consistent hits at 580 yards across a canyon, with this little SBR that fits in a backpack.

Not really a big scope (12” OAL) but I just put my Redfield Battlezone 3-9x42 on my carbine for an early next year Hog hunt. Not illuminated but with the stock out all the way and doing dry “up” drills it just fits me perfectly and is dead nuts on target. I’m pleased.
Semi hijack over.

 

[Mike_IA]

75 grain Gold Dot under penetrates on Wall board, auto glass, and plywood. It over penetrates on steel, bare gelatin, and heavy clothing in to standard FBI tests we conducted from a 16” barreled carbine gas system AR-15.

 

[tacweapon]

Does anyone know the minimum velocity needed for expansion for these rounds ?

 

[SmElly]

75 grain Gold Dot under penetrates on Wall board, auto glass, and plywood. It over penetrates on steel, bare gelatin, and heavy clothing in to standard FBI tests we conducted from a 16” barreled carbine gas system AR-15.

Any plans to perform the same testing in other barrel lengths? I'd be interested to know if the shortcomings remain in other velocities.

 

[DPapale]

Does anyone know the minimum velocity needed for expansion for these rounds ?

The number often quoted seems to be 1800 fps. How true that holds up in real world testing would be interesting to see.

 

[Arete]

A large PD that shared their results with me tested the 75 GD and afterward switched to it, found that it was expanding in bare gel at 200 yds when fired out of an 11.5" barrel. It was the only bullet that did. Most of the others turned into "super penetrators". They also tested with 16" barrels and the results were not significantly different than what they got from the 11.5" barrels.

I recently sent a bunch of 75 GD to a well known fed agency with a request to have them test it per their regular test criteria, and also at 200 yds for gel covered by heavy clothing. Not sure how long it takes to get the results, but my hope is that it'll be published in their 2019 report.

I've seen results on paper of several tests of this round out of 11.5's, and they generally chrono near the muzzle at about 2275 fps. IStrelok predicts 1850 fps at 200 yds. So, the 1800 fps guess is in the ballpark for expansion threshold, since it expanded at 200 yds in the gel test I referenced above.

Previously a Speer rep told me it might be as low as 1500 fps, but they didn't know for sure.

If you have a .gov email I can send you the results of the testing that Speer reps did with several PDs, and also testing that Speer did in house with 10" and 13" barrels.

 

[Mike_IA]

@SmElly nope. We went with 2 different rounds (federal 62gr LE223T3 and Winchester 64grn Ranger bonded) and aside from about 200 10.3” guns run all 16” weapons.