Switch from SMK's to AMAX's

[FALex]

hey folks, I just switched to 178 AMAX from 175 SMKs.

I was getting 2650fps using 42.3gr 8208 XBR and the SMKs. I am under the impression that if I used that same powder charge, the pressure would be increased due to the longer length of the AMAX, and hence the velocity would also be increased. Is that correct or am I way off?

This is going to be shot through a 24" 5r milspec.

Any input, as always, is greatly appreciated. Even if it is to tell me how poorly educated I am

 

[nicko]

Re: Switch from SMK's to AMAX's

The velocity is not going to change dramatically maybe 25 fps if I had to guess. But yes the farther the bullet is pushed in the more case pressure which will increase the velocity. But the ogive might be different and the Amax might not need to be pushed in as far it just depends on the throat depth and were the ogive starts on the bullet. You don't want to just make the smk and the Amax the same over all length.

 

[gunsnjeeps]

Re: Switch from SMK's to AMAX's

Any reason to change or just to try a different bullet? Work your load up and see how it works out.

 

[JGorski]

Re: Switch from SMK's to AMAX's

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: FALex</div><div class="ubbcode-body">hey folks, I just switched to 178 AMAX from 175 SMKs.

I was getting 2650fps using 42.3gr 8208 XBR and the SMKs. I am under the impression that if I used that same powder charge, the pressure would be increased due to the longer length of the AMAX, and hence the velocity would also be increased. Is that correct or am I way off?

This is going to be shot through a 24" 5r milspec.

Any input, as always, is greatly appreciated. Even if it is to tell me how poorly educated I am

</div></div>

I shoot 168 SMKs and AMAXs in my 06 with the same load, 50grs RE15 and the MKs hit higher at 300yds, so am I to assume the MKs are giving that load higher pressure, id think so, but the AMAXs are more accurate. I do believe the MKs have more bearing surface, thats why they give more pressure.

 

[leadbullet]

Re: Switch from SMK's to AMAX's

I tested those two bullets in a krieger 1-12 twist and with the same charge of 44 gr varget and same OAL, they hit the same spot at 600 yds, quit worrying soo much about little things that make no differences other than academic theory.
cheers.

 

[FALex]

Re: Switch from SMK's to AMAX's

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gunsnjeeps</div><div class="ubbcode-body">Any reason to change or just to try a different bullet? Work your load up and see how it works out. </div></div>

I have read on multiple sites folks believe the AMAX to be more consistent in terms of weight. Also, at my local store, they are 6.00/box cheaper!

 

[Gene Poole]

Re: Switch from SMK's to AMAX's

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: attherange</div><div class="ubbcode-body">I tested those two bullets in a krieger 1-12 twist and with the same charge of 44 gr varget and same OAL, they hit the same spot at 600 yds, quit worrying soo much about little things that make no differences other than academic theory.
cheers.</div></div>

I've had about the same performance with 175 SMKs and 178 A-Max's at 600 yd F-Class shoots. I've even used them interchangeably in a pinch. 44.5 gn Varget behind either bullet works out to 4.5 to 4.6 MILs at 600 for my stock 24 inch 1:12 PSS.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: FALex</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Gunsnjeeps</div><div class="ubbcode-body">Any reason to change or just to try a different bullet? Work your load up and see how it works out. </div></div>

I have read on multiple sites folks believe the AMAX to be more consistent in terms of weight. Also, at my local store, they are 6.00/box cheaper!</div></div>

I've not bothered checking weight distribution, but I do check random bullets for base to ogive measurement and the SMKs are definitely more consistent in this regard.

For both bullets, I seat to a tad more OAL than SAAMI. I seat to the ogive using a 0.300 datum Hornady tool and: for SMK's, 2.224; and for A-Max's, 2.186. These both result in 0.010 to 0.015 more than the SAAMI spec of 2.800, but they still feed from my magazine just fine.