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Topic: Thoughts on 140 v 142 Sierra MK's (Read 411 times) previous topic - next topic

Thoughts on 140 v 142 Sierra MK's

I'm down to my last hundred or so 142 SMK's, and am thinking about going to the 140's.  Anybody have results comparing the two?  I was shooting the Hornady 140 ELD-M's, but found they were much more inconsistent than the SMK's.  Base to ogive varied 0.020 out of the same box.

 

Re: Thoughts on 140 v 142 Sierra MK's

Reply #1
I didn't have good enough results with the 140 gr SMKs to warrant the premium, I had much better price-performance out of the Hornady 140 gr BTHPs. Just to be clear, the Hornday 140s shot better and more consistently than the SMKs out of my rifle, X-bolt 28", and they cost less.

For my 30 cal rifles the SMKs rule :)
Chris

Re: Thoughts on 140 v 142 Sierra MK's

Reply #2
I second what Bikemutt says. The Hornady 140 BTHP  shoots a very close second to my Bergers.
Live with honor and ride with courage. Be friendly to all those you meet.  But always carry a knife in your boot and a gun on your hip 'cuz there are those that don't think the same as this.

Re: Thoughts on 140 v 142 Sierra MK's

Reply #3
I tried the 140 smk when the eldm's were hard to come by.. I didnt get them to shoot near as well as the eldm's did in my gun. But in all fairness I didnt give them a really good shakedown either..
Grant

Re: Thoughts on 140 v 142 Sierra MK's

Reply #4
Timely post for me.  I've spent most of the year tuning my current 6.5 Creed and new 280 AI hunting rifles.  Just recently went back to my target 6.5 Creed and while the 140 ELD-Ms shoot very well in front of RL-16 I just ordered some 142 SMKs to see what they can do. 

I was using the 140 game Kings to fire form brass for the 140 Berger EHs and got some nice velocity and accuracy from mag length loads so I thought I give the SMKs a go.

Have a Howa HB .308 that shoots the 175 SMKs through one hole out to 300.  Always worth a shot I suppose.

Re: Thoughts on 140 v 142 Sierra MK's

Reply #5
I never did find a load with the 142 SMK's that satisfied me
with my barrel. The 140 RDF's on the other hand gave me
what I was looking for. The Factory ELD-Ms always shot good
but, for reloading purposes I tend to stay away from anything
that has an added tip....Buddy of mine shoots a 260 in his
Ruger bolt gun. His loves the Nosler partitions at mag length.

Re: Thoughts on 140 v 142 Sierra MK's

Reply #6
The 140 SMK is a dog. .535 BC is very low for that weight and caliber. I wouldn't even consider them. The 140 BTHP is better at .580. Then you step up to the .6+ bullets. Try the 147 ELDs too.

OP how did the 140 ELDs shoot? I know you measured them and weren't happy but shooting is where the decision should be made.

Re: Thoughts on 140 v 142 Sierra MK's

Reply #7
No imperical data to show, just my personal limited experience.  My rifles, bolt and gas, liked the Hornady 140s and SMK 142 much better than the Sierra 140. 

Re: Thoughts on 140 v 142 Sierra MK's

Reply #8
New to forum and new to 6.5 Creedmore.   Recently purchased a a Ruger Precision Rifle and started working up a long distance load for it.   I purchased the rifle used and it already had a scope on it, but hadn't been zeroed (seller took the high-end Vortex scope and put a mid-range Nikon in its place).   It took 10 shots to zero and produce a 3 shot 5/8" group with Hornady American Whitetail ammo.   I was/am extremely pleased with the rifle and its capabilities.   

Chose H4350 and Superformance powders paired with Hornady 140 ELD and Sierra 142 MK as a starting point.   Choices based on results seen on forums and from personal experience with bullet manufacturers.    Had never reloaded either of the powders previously, but like what people were saying about them.

So far all rounds seated to the same depth.   Haven't progressed to that stage of development yet.  

So far, the Sierra rounds have produced the tightest SD's, but the Hornady's have produced the tightest groups.  That being said, neither combination of bullet/powder has proven itself to be a clear winner yet.   Both combo's are producing sub .5 MOA groups at 200 yards and both have SD's of < 20.   Neither of which is anything to sneeze at.   Really, the only area that any component has proven to be superior is that the Superformance powder meters much better than the H4350.   This may be specific to my equipment, but for me this isn't even close.   

I will continue to work on the loads and pass info along as I go.   For now,  either of these loads looks very promising and I look forward to continuing with the research and moving out past 200 yards.  

Re: Thoughts on 140 v 142 Sierra MK's

Reply #9
Interesting so far but a proper seating depth test should be done sooner than later and each bullet tested at it's favored seating depth. Personally I'd test each bullet at what you've found to be it's best charge weight so far from -.014 off through -.029 off in .003s

The sooner you get seating depth nailed down the sooner you can fine tune powder IMO
Dave

Re: Thoughts on 140 v 142 Sierra MK's

Reply #10
Neither of my F-Open rifles shoot the 140's but both like the 142's.  I weight sort them and use them for local matches and Mid range and save my Burgers for big matches.