Stick with 175 smk or change to 178 amax?

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Jethro21

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Minuteman
Sep 23, 2011
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Phoenix,Az, USA
#1
So I have been shooting 175smk's and was loading some different OALs which got me a little frustrated. I had trouble getting consistant OALs so I started to measure the bullets themselves. I found that they varied from bullet to bullet up to .005. I am not super anal about things, but since I am still developing my load I want the most consistancy I can get.

I know I can but a meplat trimmer, which I might, but I was also thinking that the 178 amax may be more consistant because of the polymer tip...

So my question is, has anyone measured the 178's and found they are more consistant in length? Is it worth it to buy the trimmer or change bullets?

Thanks,
Jethro
 
#2
Re: Stick with 175 smk or change to 178 amax?

My $0.02:

Don't sweat it. Any real or perceived difference in the bullet consistency (with these particular bullets, anyway) is NOT going to show up on target.

I would encourage you to try both (and more!) bullets, but don't dump the 175 because you're seeing a few thousandths inconsistency.
 
#3
Re: Stick with 175 smk or change to 178 amax?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jethro21</div><div class="ubbcode-body">So I have been shooting 175smk's and was loading some different OALs which got me a little frustrated. I had trouble getting consistant OALs so I started to measure the bullets themselves. I found that they varied from bullet to bullet up to .005. I am not super anal about things, but since I am still developing my load I want the most consistancy I can get.

I know I can but a meplat trimmer, which I might, but I was also thinking that the 178 amax may be more consistant because of the polymer tip...

So my question is, has anyone measured the 178's and found they are more consistant in length? Is it worth it to buy the trimmer or change bullets?

Thanks,
Jethro </div></div>

I hope you are not measuring to the tip of the bullet..You only need to be measuring from the ogive and totally disregard those tips. When I started reloading I was measuring from the base of the case to the tip of the bullet and would then change the seating die so that each round had the same COAL. This is wrong way wrong don't do it. You need to measure from the base to the bullets ogive, as that is what hits the lands, and is also where the bullet seater touches to seat the bullet.


If you want to you can weight sort the 175smk, then measure from the base of the bullet to the ogive, and then load them.
The 178 amax is not as jump tolerant of a bullet as the 175smk.
 
#4
Re: Stick with 175 smk or change to 178 amax?

+1 on turbo54 and frankythefly. What kind of seating die are you using? Most seat from a datum near the ogive so COAL will vary anyway, but the rifle only cares about ogive since that's where the bullet hits the lands. I've personally had good luck with both HPBT Sierra's and A-Max (leaning a little more to the A-Max side).
 
#10
Re: Stick with 175 smk or change to 178 amax?

I will have to look how to measure to the ogive and will try that for my remaining 175s, but I think I am going to give the 178s a go as well. Thanks for the help guys
 
#11
Re: Stick with 175 smk or change to 178 amax?

Depends.

If you are loading to a precise length and wanting to optimise for precision then the AMAX may be better as it has a slightly better bc as a result of its secant ogive. Downside is that it may not be as precise if you don't.

SMK trades a bit of BC for some length tolerance from its tangent ogive. It may shoot better if you just stuff them in to magazine length. Also LOTS of load data with 175SMK which is a plus.

If you are not chasing ultimate precision then this is all very interesting but not really very helpful as you will not really see much difference. I don't shoot 175 SMK as I can't find them and therefore shoot the AMAX range as I can get them and they are a bit cheaper (also they behave like the VMAX)
 
#12
Re: Stick with 175 smk or change to 178 amax?

My 175 SMK, 178 A-Max story:

I found some guys here that were killing animals with A-Maxes and decided I would give them a try since I was in search of a good hunting bullet.

I ordered a box of 100 and loaded them to the exact recipe as my 175 SMK load. I didn't adjust powder charge, seating depth or anything else. I just loaded them with the bullet seater die set in the same place as it was for the 175 SMK. Which gave it a longer OAL, but like others have mentioned, it was the same length to the ogive.

I went to the range to prep for a match and set steel from 200 to 700 yards. I ran through the targets dialing for the Match King, leaving elevation on the scope alone and sending an A-Max right behing the Match King out to 700 yards.

The end result was (don't have my log book in front of me) that the A-Max shot dead nuts with the Match King to 300 yards. Beyond 300 yards it was between .1 MIL to .3 MIL above the impact of the Match King (it shot flatter!)

After that experiment I decided to load up 30 rounds to place in my ammo wallet I take hunting. I didn't get a shot on a deer, but I did hit two coyotes. One at 150 yards the other at 180 yards and it was devastating. The next day I hit a 350 pound hog at 100 yards and it droped him in his tracks.

I'm an A-Max fan, without a doubt.
 
#13
Re: Stick with 175 smk or change to 178 amax?

Garvey: that's a great write up. I have gone to the range with both bullets loaded and never thought to do that. I do load the bullets with the same charge. Getting 2700 out of a 22". I dont have enough data, but my gut tells me the SMKs shoot better to 300 and the Amax shoot better at 600.
And now, I just bought two boxes of Berger 175s to try. OTM: is that just another way to say HPBT?
 
#14
Re: Stick with 175 smk or change to 178 amax?

Thanks for the positive feedback. I felt like it was ballsy to not start from scratch working up a load for a new bullet but it worked out just fine.

I told the friend that was with me that day "damn, this is going to be my hunting load, I could hit out to 700 yards with it, I won't but I could." He said "hell, why not you've hit everything you've pointed it at!"

The results I got were from a Savage model 10, 24" barrel with a 1:10" twist. When I found the node with the SMK (a year prior) it was chronoed at 2720 fps. I didn't chrono the A-Maxes but it was apparently moving somewhat faster.

I havn't measured the A-Maxes but when performing a visual inspection they are way more consistant bullet to bullet than SMKs by a significant margin. Obviously that is a positive feature of a polymer tip vs. a fine hollow point.

 
#17
Re: Stick with 175 smk or change to 178 amax?

Give the 178 match hornady a look as well.

My 175smk load is 45.5 varget @ 2675 (max load) according to my chrono, but to get my trajectory matched up, I have to use 2750 in the calculators.

Today, I ran ladders with the 178hpbt and got 2745 on the chrono @ 46.34gr prior to pressure at 46.66gr.
 
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