30 cal Bullet cuts

[ejg223]

Just out of interest.

left to right

Hornady 150gr SP interlock, 150gr Nos BT, 155gr A-max, 165 SST, 165 Nos BT, 190gr SMK

 

The 150gr SP looks as if the jacket is very flimsy, or?

 

edi

[Chris-NZ]

You either have too much time on your hands Edi, else you've delegated to the Engineering Dept

 

Good pics, interesting how thin the jacket is on the Interlock. Doesn't look to have much locking in the design..

The Ballistic Tips are way thicker than their reputation would suggest, mind you, the heavier calibre ones are by reputation more robustly built in recent times.

 

Chris-NZ

[Ronin]

My guess is the Interlocks are a bonded core so do not rely on heavy jacket..

 

 

Interesting the SMK has what appears to be a very un uniform jacket wall thickness (unless its me) one would expect the wall to be the same both sides.

 

 

You may have a future in sectioning Edi, be careful the German doctor doesn't take you under his wing, you'll be doing humans next

[Streeker59]

Judging by the unequal wall thickness of that SMK, that bullet wont turn as it goes downrange.... It'll trundle and loop the loop...

If that's the general quality of Sierra bullets now, i'm glad i made the move to Berger..

 

Edi, you should email that pic to Sierra to see what they comment...

[ejg223]

Thanks,

the SMK does have a uniform wall section , thickness as on the left.

The problem with this soft copper is that while milling it smears into the lead.

Main reason was to see the difference between a designated game bullet and a

target bullet. If the interlock is not bonded, which I don't know, then it's as thin

in the jacket as an a-max. The front of the a-max is similar to the sst.

Maybe the interlock is an old design more intended for a slowish 30-30 or 308.

 

edi

[ejg223]

My guess would be to to even out the the expansion rates.

The copper jacketing would be heavy enough to punch hide and

muscle....but not quite heavy enough tp punch bone with out the

reinforcement of the lead underneath.

 

Run a hardness test on the lead cores to see whats what...

I think the lead will be a little bit harder in the interlock...then an A-max

 

308Panther

 

Pat,

don't have a hardness tester. I could re-rig my tensile strength machine to compare but... jaysus..

It would explain things though.

 

What I find interesting is that we see as big a difference between game bullets as between game and target bullets.

 

An important factor I presume is the diameter of the soft opening, the larger plastic diameter of the Nosler could be responsible

for the reputation of having rapid expansion.

[devilishdave]

Interesting, the A MAx looks on face value that it would be atleast if not more explosive than the SST due to a very similar front end and a thinner wal and base. The Lead and copper may have different properties which could make a significant differance.

 

Dave

[Vermincinerator]

While we are on the subject of Sierra Matchkings take a look at this pic:

 

 

It shows two .257" 100grn SMKs form the same box, there were 48 of one size and 52 of the other.

Although the weight was within 1/10 of a grain across all 100 bullets there was a substancial difference in OAL and base to ogive length.

There was a .035" to .058" difference on the OAL between the long ones and the short ones and .048" to .056" difference in base to ogive.

You can also see a visible difference in the ogive shape.

I sent an email to Sierra with the accompanying picture and the batch numbers of the bullets back in November.

I got a reply a week before Christmas asking for my contact details as they had gone a miss.

I had another email from Sierra on the 27th January stating they are working on this and hope to have some information for me soon.

To be honest i was not expecting Sierra to reply at all, so at least they have taken an interest in my problem bullets.

 

Ian.