Swift Scirocco and M14

Chuk4blast

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Anyone use a Swift Scirocco 168-gr in M14 for hunting , just curious on anyone's experience or knowledge thereof, I'm trying something new. Thanks
 

budlight

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I don't know if this helps, but I have a 24 in AR10. I worked up some loads with 168 Berger classic hunters. G1 BC of .496 I bought 500 back when Midway sold them for about 33 cents each. They are quality hunting rounds.

I did a bunch of chrono/bench time and settled in on Ramshot Big Game powder and 2720 fps.

I use commercial cases for the extra powder volume. I got away from mil brass because I would follow a reloading data and end up popping primers from time to time. I also had these problems using the listed magnum primers.

So I only use large rifle standard, commercial cases, and neck turn when required.
 

rammac

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I've been reloading for the M1A rifles for several decades and the most versatile powder I've found is IMR 3031, it's a good powder to start with and use as a base to compare against.

I assume you're referring to the 165 gr Swift Scirocco since they don't list a 168 gr bullet.

A good starting starting load would be;
Case trim to length of 2.006"
Cartridge overall length of 2.80"
From 38 to 41.5 grains of IMR 3031

Another powder that will work well is W748
From 40.0 to 43.0 grains would be a reasonable range of powder charges.

As always, start low and work up in powder charges, you'll know if you're too low with the M1A because the system won't cycle.
 
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budlight

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look at https://www.hodgdonreloading.com/data/rifle I've always stayed away from fast from fast for the caliber powders like 3031. You can see the the pressure is really high compared to say a modern powder like CFE 223 to get the same FPS. The copper foul reducer powders really do work!

I would rather burn more powder at a lower pressure to get the same velocity.
 

rammac

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look at https://www.hodgdonreloading.com/data/rifle I've always stayed away from fast from fast for the caliber powders like 3031. You can see the the pressure is really high compared to say a modern powder like CFE 223 to get the same FPS. The copper foul reducer powders really do work!

I would rather burn more powder at a lower pressure to get the same velocity.
Where do you see that IMR 3031 has high pressure?

Your link doesn't even show any .308 Win IMR 3031 loads.
 

budlight

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Where do you see that IMR 3031 has high pressure?

Your link doesn't even show any .308 Win IMR 3031 loads.
I don't know what to say to you...... if 3031 takes a pressure spike of near the upper limit of psi to get the same fps of a modern slower powder with 9K less pressure. What don't you understand about the hodgdon reloading link I posted?

Online reloading....... you have to input some data like caliber, bullet weight and powders;)


Hodgdon
CFE 223
0.308"
2.800"

41.0
2,444
39,600 PSI

45.0C
2,664
49,800 PSI

IMR
IMR 3031
0.308"
2.800"

38.0
2,493
46,600 PSI

41.5C
2,693
58,600 PSI
 

rammac

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I suspect that you didn't notice that there are two sets of loading data for the .308 Win; one for the standard bolt rifles and one for the service rifles. You obviously were incorrectly looking at the bolt rifle data while I was looking at the service rifle data since that's what the OP asked about. Now that I've figured out that you are looking at the wrong data I see the IMR 3031 load information.

The first problem is that you are using the Hodgdon data for an M1A service rifle. Hodgdon isn't all that reliable for most of their load data in my opinion but their .308 Service Rifle data is absolutely wrong. They show that their service rifle data was developed using a 24 inch barrel, I don't know what 7.62x51mm or .308 Winchester service rifle they used but it could not have been an M1A since they've never made an M1A with a 24 inch barrel. Hornady, on the other hand, developed their load data using an M1A rifle. Comparing the data from each will prove that Hodgdon is completely unreliable for M1A data.

The bullets used in each manual are different so the data isn't a perfect comparison but it's pretty close if you compare a Hornady 168gr Amax to a Sierra 168gr HPBT. Using those bullets and IMR 4064 (neither Hodgdon nor Hornady show IMR 3031 with this weight bullet so I used IMR 4064 since both show load for it);

Min Powder ChargeMaximum Powder Charge
Hodgdon Manual41.5gr 2518 FPS 43,800 PSI43.9gr 2653 FPS 52,000 PSI
Hornady Manual36.1gr 2100 FPS 41.6gr 2500 FPS

It's obvious that Hodgdon's data is very different from data that was developed by testing in a M1A rifle. What's more telling is that if you check out Sierra's data it's very close to Hornady's data (taking in to consideration that Sierra used a 24 inch barrel for their testing). Note that the max powder charge in Hornady's manual is almost the same as the min powder charge in Hodgdon's manual. It is common to find that the M1A rifles will produce a muzzle velocity of around 2550 FPS using a 168gr bullet when you use a powder that is well suited to the design of the rifle's action. So Hornady's 41.6gr load is very close to that traditional combination. And while you might want to claim that Hodgdon says that that is a good powder charge too but then says that you can go up from there, you have to remember that Hodgdon didn't use an M1A for testing and that over the years many M1A shooters have found that anything more than 2550 FPS with a 168gr or heavier bullet is not good for the rifle. Long range National Match shooters will push their rifles with hotter loads but they also replace barrels quite often and they actually do see the receivers crack from time to time.

The next problem is that the Hodgdon data used the Barnes TTSX and the Sierra HPBT bullets for their bolt gun data and just the Sierra HPBT bullet for their Service Rifle data, neither bullet is very similar to the Swift bullet. The Swift bullet is actually a 165gr bullet that is much shorter than the other bullets. That means that the pressures and velocities shown in the Hodgdon data isn't going to match up very well with the bullet that the OP wants to use.

While CFE223 does produce higher velocity at lower max pressure (under the TTSX bullet) it also produces higher port pressure for the M1A rifle which will batter the action and create excessive wear compared to IMR 3031. In fact, I would never recommend using 41.5gr of IMR 3031 under the TTSX bullet because the max pressure will actually be higher than Hodgdon claims and it will definitely create premature case failure and excessive wear on the rifle's action. I recommended a max powder charge of 41.5gr of IMR 3031 only because the OP is using the Swift bullet and its shorter length provides more usable volume in the case and the pressures will be lower.

And finally, I've tried using CFE223 in my M1A rifles and can honestly say that it didn't produce the kind of accuracy/precision that I get from IMR 3031. So between my personal experience and pressure data that I believe is accurate, CFE223 is NOT a good choice for an M1A rifle.
 
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budlight

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I can see what you are saying. I have Ar10-308's with rifle length gas and extended gas tubes with 24 inch barrels that don't experience the higher pressure of shorter tubes.

Just for the record our rifles in the military were M14 with select fire. About the time we were getting out we got got some m-16's like the regular service branches and I thought what a phony weapon
 
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