Introducing the 7.62X40-the new .30 caliber AR solution

[Altair]

Alright gentlemen,
I like all these cartridges. Maybe I just like cartridges! But I do like all this experimentation. You guys are doing great work. I like this 30 cal because it sticks to the original bolt face and that sort of helps keep cost down. But I STILL love these 6.5 rifles just because of the numbers they put out. Unlike my ex wives numbers never lie. So has anybody out there tried the old 6.5 TCU. Back in the day I did a bunch of load dev elopment for this cartridge in a bolt action Remington pistol. It was and XP100 or something like that. Bottom line...It was HOT. It was accurate as hell. We used it on rock chucks by the hundreds but I would have shot any deer with it. Certainly much better than a 223. I know its about shot placement. Afterthat though its about penetration and damage done. Ok guys. What do we think?

6.5 TCU has been done in the AR but has some load length problems. The 6.5 MPC, done by JD Jones of SSK (same as the original 300 Whisper), has been around a while. It is basically a .223 necked up to .264 and trimmed back. Also, there are a couple guys on AR15.com have a long thread about the 6.5PCC, which is a modified TCU designed for the AR.

[Warhawk]

This is addressed to the Wilson Combat folks ...

I see that you have some 7.62x40 barrels on sale. I am undecided between the 16 inch match fluted barrel, and the 16 inch lightweight hunter.

I intend to handload for this, and don't want a tight match chamber. Are the chambers different on these barrels?

[wilsoncombatrep]

The chambers are the same on all of our 762x40WT barrels.

[Altair]

I've been doing some testing on .224" bullets using water jugs and have learned some important information so I decided to try a couple from my 7.62x40. I've had the 110gr TSX and the 110gr TSX-SBR for a while and wanted to see what they would do. Barnes told me that the upper velocity limit on the SBR version (which was designed with the 300BLK in mind) was around 2300fps. I get 2500fps from these bullets in my 16" 7.62x40 so I figured I would just hold on to them for use in my 300BLK or my 7.62x40 SBR (when I get it), but I decided to test it from the 16" today just for fun.

Here's what I found. Both bullets had an impact velocity of approximately 2470fps (10 yards from the muzzle). The standard 110gr TSX mushroomed perfectly, as I've come to expect from the TSX line of bullets, and completely penetrated 4 jugs of water, coming to rest in the 5th. It had 100% weight retention and expanded to 0.641".

Next up was the 110gr TSX-SBR. After having quite a few of the .224" TSX's lose their petals if driven to velocities above what Barnes recommends, I expected the SBR bullet to do the same at this impact velocity, however, it did not. It also exhibited a perfect mushroom, but it expanded further down the shank of the bullet. It penetrated 3 jugs completely, and stopped in the 4th, which suggests it opened earlier and lost more energy but had a shorter neck length than the standard TSX. It retained 100% of its weight and expanded to 0.656".

Also of note was that the standard bullet penetrated similarly to a 62gr TSX from a 5.56 rifle and the SBR bullet penetrated similarly to a 62gr Bonded Federal .223 round so penetration should be about right for hunting and defense. I know milk jugs are not hogs or humans, but the bullets both held up well (surprising so for the SBR bullet), and penetrated well.

Since the SBR bullet held together so well, I'm thinking it may be about perfect for the 7.62x40 as it would increase the effective range considerably. The standard TSX is supposed to expand to 1800fps (220 yards with a MV of 2500) and the SBR bullet is supposed to expand down to 1500fps (330 yards with a MV of 2500). These may be worth looking at.

Just for comparison I also shot a 110gr V-Max into jugs. It completely penetrated 2 jugs leaving fragments in the first two and the jacket and core stopped in jug 3. It only retained 38.3gr (34.8%) and the core expanded to 0.579".

Here are some pics:
Standard TSX on the left, TSX-SBR on the right


The V-Max

[piperpilot3tk]

The bullet you are referring to is called the TAC-X. I have loaded the 62 grainers and shot stacks of wet phone books at 100 yards with my M4. These bullets rock, they penetrated four phone books and continued to penetrate two and a half feet of wet dirt, they expanded to approx. .485" and had zero petal separation or weight loss, I also shot M855 at same set up and they were recovered intact yet badly deformed in the third phone book. I will be loading some of the .30 cal bullets for my 300 BLK SBR!

[Altair]

The bullet you are referring to is called the TAC-X. I have loaded the 62 grainers and shot stacks of wet phone books at 100 yards with my M4. These bullets rock, they penetrated four phone books and continued to penetrate two and a half feet of wet dirt, they expanded to approx. .485" and had zero petal separation or weight loss, I also shot M855 at same set up and they were recovered intact yet badly deformed in the third phone book. I will be loading some of the .30 cal bullets for my 300 BLK SBR!

According to Barnes the Tac-X and the TSX are identical (provided you are talking about the same caliber and weight). Barnes sells a 110gr TSX, a 110gr Tac-X, and a 110gr Tac-X SBR. The first two are the same but sold under two different names to appeal to two different markets. If you want them for a 300BLK (especially an SBR) make sure to get the SBR version, they are designed to work at a much lower velocity window.

[rsilvers]

The SBR is called SBR because it is designed for 308 SBRs. There was just not much demand for it until 300 AAC BLACKOUT came out - so that is when they released it.

If you are shooting under about 2600 fps, or want to shoot at longer ranges, I would select it over the normal one.

[macvrlamm]

so has there been any more work on the 762x40 as I have more than a passing interest in these weapons they seem to be an almost perfect combination of parts for a light heavy hitter

[BWilson]

so has there been any more work on the 762x40 as I have more than a passing interest in these weapons they seem to be an almost perfect combination of parts for a light heavy hitter

Biggest news is the new bullet Barnes designed specifically for the 7.62x40WT, it's designed to reliably expand down to 1300fps impact velocity with optimal expansion in the 2100-2400fps (impact) range. Accuracy is very good and so far the 9 hogs we have shot with the bullet were VERY impressed............... This bullet definately increases the effectivness of the round on bigger/tougher game.

Barnes #30801
110gr TTSX LV (low velocity)

Available exclusively from Wilson Combat until after the SHOT show 2012

[constructor]

Thanks for working with Barnes to bring the new 30cal and 6.8mm bullets to market Bill. IMO proper expansion can make a huge difference in terminal performance and using 308 win projectiles at slower speeds does not always work so well.