175 vs 180 Sierra MK's

[diderr]

Since 175 match kings are unobtainable right now is there any draw back with using the 180's in a 308? I know the ogive is slightly longer. I was going to use Bergers since I've always had good luck with them, but I wont be able to use my mag if I went to the coal I needed, and they're $15+/- more a box. My throat is for 180's and I'm running a 1 in 10.
thanks.

 

[1lnbrdg]

The 180gr Sierra's will make it to 1K but barely. The heel of the bullet is the same as the Sierra 168's and they don't fly well, loose velocity like crazy. Still, a pretty good bullet to 800 yds though but then so is a 168.

I'd love to have some of the older Sierra 180's with the longer boat-tail. Those were good bullets.

 

[Dan Newberry]

I've shot them... 1lnbrg is right, they'll wanna face plant early, but if you can get them up to 2550 or 2600, they'll get the job done. They are very accurate, for sure.

I found them to actually fly about even with Nosler's 180 grain BT, which has an apparently over-rated BC of .500...

But we're living in a time when we've got to make what we can find work. If all I could find was the 180's, I get them and run 'em... Varget will get you and easy 2600 fps off of them, and that'll make 1000 yards--if you're going that far.

Dan

 

[ksthomas]

The old style 180 SMK was a pretty good bullet, and very popular with most Service Rifle shooters for their 1,000 yard matches. No problem staying supersonic all the way out, decent accuracy and not at all fussy to work with. They did indeed change to boat tail angle and length, to be able to reduce tooling and allow them to use the same set-up that is used on the 168s. Totally destroyed the bullet, and its been nothing more than a paperweight ever since.

The 175 came along later at the behest of LCAAP for revamping the M118, then loaded with the 173 FMJBT. The new 175 gave similar ballistics as the 173 (which was quite good all the way out to 1,000), and accuracy on par with the M852 Match ammo that we then loaded with the 168s. The M852 shot beautifully, and hit a brick wall at about 900 yards. Berm shots, keyholing and tumbling bullets (when they hit the paper), the whole deal . . . it was ugly. The 175 solved the problem and rolled both up into what has since been known as the M118LR. Good stuff.

Use the 180s for shorter range stuff and don't try to stretch them to 1,000. They shoot just fine at the shorter range.

 

[turbo54]

Varget will get you and easy 2600 fps off of them, and that'll make 1000 yards--if you're going that far.

Dan

It's been a while since I used the 180smk, but that is ALL I used to shoot (before I knew better). I was not able to achieve 2600fps. 43.0gr Varget was a max (but safe) charge and that netted me 2540-2560fps. I'd usually run 42.5gr Varget, and that would give me 2500 pretty much right on the button.

The rifle was a Savage, and it wore it's 24" factory barrel back then.

I also ran these through my FN SPR A3G when I first got it - also a 24" barrel, and it's velocity was right there with my Savage.

I've shot them at 1000 yards and I found them to actually run pretty consistently. They weren't doing anything crazy downrange, far as I could tell, because I could hit 12" steel with pretty good consistency if the wind was calm, and my misses were always close.

There *were* falling out of the sky, though. ~45moa up from 100 yard zero, if I remember correctly.

 

[diderr]

The old style 180 SMK was a pretty good bullet, and very popular with most Service Rifle shooters for their 1,000 yard matches. No problem staying supersonic all the way out, decent accuracy and not at all fussy to work with. They did indeed change to boat tail angle and length, to be able to reduce tooling and allow them to use the same set-up that is used on the 168s. Totally destroyed the bullet, and its been nothing more than a paperweight ever since.

The 175 came along later at the behest of LCAAP for revamping the M118, then loaded with the 173 FMJBT. The new 175 gave similar ballistics as the 173 (which was quite good all the way out to 1,000), and accuracy on par with the M852 Match ammo that we then loaded with the 168s. The M852 shot beautifully, and hit a brick wall at about 900 yards. Berm shots, keyholing and tumbling bullets (when they hit the paper), the whole deal . . . it was ugly. The 175 solved the problem and rolled both up into what has since been known as the M118LR. Good stuff.

Use the 180s for shorter range stuff and don't try to stretch them to 1,000. They shoot just fine at the shorter range.

Good info. thanks. Good thing I didn't buy them then. I'm going to be primarily shooting from 600 to 1000 yards.

 

[tactserv]

180gr SMKs

The 180gr Sierra's will make it to 1K but barely. The heel of the bullet is the same as the Sierra 168's and they don't fly well, loose velocity like crazy. Still, a pretty good bullet to 800 yds though but then so is a 168.

I'd love to have some of the older Sierra 180's with the longer boat-tail. Those were good bullets.

I scored a bunch of them (~12K) and am working up a good high speed load that groups well but doesn't eject the brass out in pieces ;>0

If only I could find out what the BC of them is. Seirra folks I talked to do not know.

Mike

 

[tbugher62]

Hi,I have a 1000rds of 308 SMK 175gr bullets,500 rds of once fired Fedreal Gold Metal 308 brass (fully proccesed )and 900 Fedreal Gold Metal Match primers that you can have for $500.00 shipped.

 

[ksthomas]

Tactserv,

The guys at Sierra couldn't tell you what the BC of the old 180s was???? I can dig that up for you, no problem. Kind of embarrassing that they couldn't/wouldn't do that for you. I want to say it was around .515 (G1, of course) but I'll have to look at some of my old notes.



------UPDATE------
Just checked in the Sierra First Edition Manual on the shelf. The BC of the original 180 MK (long BT design) is listed at .535. As I said, it used to be a good bullet.

 

[armydog]

I found a G1 of .482 but that was from Bryan Litz's data so it may be closer that Sierra's advertised.

 

[cjherrman]

Some of this is also going to depend on what YOUR particular rifle likes. I have had good luck with them.