Suggested load for .308 winchester using generic MidwayUSA 220 grain HPBT bullets

[RooftopKorean]

Anyone have any suggested load data for these bullets? I picked them up because they were on sale at MidwayUSA.

Hornady manual has for ELD-X or Interlock RN, not HPBT
Lee Modern Reloading doesn't go up to 220
Lyman Handbook doesn't go up to 220
Western Powder's Handbook doesn't go up to 220

Would be firing from my M1A 1:11 twist

 

[thegatman]

The problem with 220 grain bullets in a .308 is that you don't really have enough case capacity for powder and most barrels aren't long enough to utilize the slow powders used for the "heavies".

This is why you don't see loads listed for the 220 gr bullet. It's more for 30-06 and other 30 cal "Magnums".

 

[RooftopKorean]

The problem with 220 grain bullets in a .308 is that you don't really have enough case capacity for powder and most barrels aren't long enough to utilize the slow powders used for the "heavies".

This is why you don't see loads listed for the 220 gr bullet. It's more for 30-06 and other 30 cal "Magnums".

Ahh, well thank you. I guess they are useless until I buy a 300 win mag rifle.

 

[spat]

Ahh, well thank you. I guess they are useless until I buy a 300 win mag rifle.

Well, you can load them up and safely shoot them, they'll just be a bit slower than optimal.

Kinda like having a high HP racing engine in your car, but just factory tires.

 

[BDinPutnam]

Ahh, well thank you. I guess they are useless until I buy a 300 win mag rifle.

Do it. I love mine.

 

[thegatman]

Ahh, well thank you. I guess they are useless until I buy a 300 win mag rifle.

Or a 30-06.

 

[meketrefe]

Old timers used to load budget heavy 200gr loads all the time until with modern bullets
one went with flatter faster shooting rounds. Heavy loads are still a good choice for close work on
heavy game like alaskan folks to take down a big bear or a moose although they are better choices
like a 358 from the same 308 case or a heavy 30-06 or a whelen or a 338 magnum that are more typical.

220gr is not the ideal choice but if it works there will be just slower loads but with lots of momentum
and more recoil, obviously.

In order to know if you can load them or not we need some information:

A) barrel length?
B) rate of twist is 11 right but what about the bullet, what is the bullet brand and precise model? construcion, material, shape and therefore length is a huge factor to know if they will stabilize. the manufacturer might also tell you.
C) Also what is the maximum COAL you can manage as imposed by the freebore or the magazine (unless you single feed) whichever comes
first? The best thing would be to take an empty case and to neck size it just so slightly so you can find out your freebore.

Initially...
CFE is a great power for this same as Ramshot big game.
Varget and AA4064 could work too but the other slower powders will work better.
If you get decent coal you can start with the same starting loads of a 208-210gr bullet given
they will stabilize that will not be a no no if they are VLD/match bullets that are also longer.

 

[RooftopKorean]

@meketrefe

SAI M1A SOCOM 16, 16.25" barrel

The bullet is 1:12 twist repackaged factory second match grade, length of 1.5030.

The Hornady Tenth Edition calls for CFE223 at 37.0gr for a 220 gr. Interlock RN for 1900 FPS. Maximum COAL 2.810.

Lee Reloading Second Edition calls for Accurate 2520 at 37.3gr for a 210 gr. jacketed bullet for 2402 FPS.
Minimum OAL 2.810

General concensus with M1A shooters is 2.810 max COAL so i say the books are both spot on.

 

[meketrefe]

@meketrefe

SAI M1A SOCOM 16, 16.25" barrel

The bullet is 1:12 twist repackaged factory second match grade, length of 1.5030.

The Hornady Tenth Edition calls for CFE223 at 37.0gr for a 220 gr. Interlock RN for 1900 FPS. Maximum COAL 2.810.

Lee Reloading Second Edition calls for Accurate 2520 at 37.3gr for a 210 gr. jacketed bullet for 2402 FPS.
Minimum OAL 2.810

General concensus with M1A shooters is 2.810 max COAL so i say the books are both spot on.

This is good info. Thanks.
do you want them to load from the magazine? If so what is the max COAL of your actual magazine?
I have several M1A mags that allowed me to load 2.850-2.870 and they are about 10-20 thousands off the lands.
The book and forums are only general guidance but cannot know what magazine or chamber do you really have
and with that all the possibilities to get a bit extra case space, more accuracy and everything else.
If you don't want to find out and a 2.830 or 2.840 feeds and chambers fine it should be a good start.
16" barrel is not going to be fast but it will work if it stabilizes, that is the big question.

37gr of CRF or 2520 look like good starting loads and you will be able to work them up. 37gr of varget should
also be a good starting load according to the actual manufacturer of the powder.

Midway seconds could be hornady or Nosler, in this case possibly a Nosler Custom competition but
then the length doesn't seem right. Did you actually measure the bullet length to be a 1.5030 average/spread?
I am asking because I don't recall any other 220gr Match BT around that lenght and nosler are a tad longer and also
in that case 11 twist is going to be hard to stabilize but it could.
The 11 twist is going to be cutting it really close and the 12 twist above is probably form the books for round nose
hunting bullets that are shorter so it is all typical reloading manual arbitrary and sometimes erroneous or
misleading information.

The best way to find out is as I described earlier:
- measure your bullets
-Find out your actual max coal dictated by your own chamber/lands or your own magazine (lets say it allows you for 2.850)
like my M1A magazines and chamber did.
-Just load 3 rounds with the starting load and see if they stabilize at 50 yards. If they don't, stop, and save the
bullets for another project or trade them and if they do then continue with load development.

I hope this helps. Good luck.

 

[RooftopKorean]

@meketrefe I measured the Midway seconds bullets with my digital calipers. I also did check various forums and they say max OAL for magazines is in line with what the books suggested at 2.810 and that's the SAAMI max length spec as well.

I pressed a dummy round and it does fit the magazine at 2.85010 and it chambered but after remeasuring it compressed down to 2.84045

I guess I will make three rounds as you suggested and give them a go next time I visit my friend in PA.

 

[meketrefe]

@meketrefe I measured the Midway seconds bullets with my digital calipers. I also did check various forums and they say max OAL for magazines is in line with what the books suggested at 2.810 and that's the SAAMI max length spec as well.

I pressed a dummy round and it does fit the magazine at 2.85010 and it chambered but after remeasuring it compressed down to 2.84045

I guess I will make three rounds as you suggested and give them a go next time I visit my friend in PA.

Yes bring other ammo and those 3 loads to see if they stabilize and that way you will know first hand if it is worth continuing load development.
Give them at least 50-75 yards to see if they stabilize.

It seems that you could load them at 2.830 that is pretty common for some smk and nosler CC match loads for M1A and AR10 regardless of what any other forum say. Remember not all chambers are equal even the same model rifle from batch to batch and year to year will use a different reamer spec/model and reamers also wear out and whatever the machinist might do.
If these were 150gr fmj burners I would say stick to 2.810 or even less, depending on bullet cannelure and other things but
otherwise stick to what you just found out from your own setup.
Again the tricky part is going to be stabilizing that seems right on the edge of what you can do for that bullet length and speed.
If they stabilize you should be able to squeeze some extra 200fps with careful load development.
If they work, the nice thing will be that if you want to shoot tactical steel targets you will have no problem in scoring in old rusty gates
unlike the 6 and 6.5mm rounds because you will get lots of momentum out of those bullets.
Next time don't go over the 180-185gr for a lead core bullet with the 308.

Let us know if you get them stabilized and how that works. Good luck.

 

[RooftopKorean]

So stupid question, how do I know if they are unstable/stable? Accuracy?

 

[meketrefe]

So stupid question, how do I know if they are unstable/stable? Accuracy?

there is never a stupid question, only stupid answers. lol

Worse case: you get a Key hole on the target that means stop. don't waste bullets.
Look for accuracy and uniformity (roundness) on the paper/sticker holes.
Uniform bullet impacts will have a nicely done paper punch with an edge of carbon all around.
Accuracy is what you want anyway (repeatability) even if it is in the boundaries of the stabilization range.
It is not like you are going to shoot long range with a 16" barrel I am sure so if they stabilize at 10-75 yards
they should be good for half mile or perhaps a tad less before they enter trans-sonic range and start to
wonder again. That is why subsonic match bullets need a much faster rate of twist that would be an 8 or faster
wiht this type of bullet, that is a waste of match bullets anyway. Sub work is another complete ball game anyway.
Makes sense?

 

[repete]

So stupid question, how do I know if they are unstable/stable? Accuracy?

What ^^ he said, If you can find some foam targets you'll see right away if the bullets keyhole or not! I kept a target for years and tossed it out just last year. It showed a .54 maxi that went totally sideways thru the target way off to the right and high while two other rounds where pretty much centered. The key hole was perfect, it even showed the lube grooves! I believe that was caused by a void when casting the bullet.

 

[RooftopKorean]

So basically a nice round circle and not a line (is that what you mean by keyhole?) which would mean its tumbling and not stable.

The game land by my buddy has 150, 100, 50 and 25. I'll range out at 50 first and if its OK i'll move on to 100.

 

[meketrefe]

So basically a nice round circle and not a line (is that what you mean by keyhole?) which would mean its tumbling and not stable.

The game land by my buddy has 150, 100, 50 and 25. I'll range out at 50 first and if its OK i'll move on to 100.

Yes. you will see the holes. if it is not sighted you might want to move closer or sight with other round and then hold the shot high at 50 yards so you will get your impacts on the paper, hopefull with some hope for accuracy too. ...or will spend your 3 bullets w/o getting the
impact on the paper. Also make sure paper is large and well secured and target not canted but squared with your position
that way you can get the best prints you can.
Hopefully they will stabilize. I am curious since you are right on the edge in terms of stability factor for those type of bullets.
The length and the bullet construction and weight distribution+speed is more important than anything else here.
heavy SMK or berger will stabilize in a 11 twsit (they are longer) but if it is a nosler CC there is a better chance.