Surprised @ difference between Siera & Hodgdon loads for 168 SMK

[Linko]

Despite the cost, it's always best to start with new brass and once you have loads you're happy with stick to it. Most makes are good nowadays, but you may well get the extra outlay back and a bit more by buying Lapua (and maybe Peterson which looks to be as good) cases as you'll likely get more firings out of them.

Winchester was long reckoned to be good for the price bar a few damaged examples in most baggies. However, there is widespread dissatisfaction becoming evident these days from formerly happy purchasers thanks to the number of 'issues' with recent production lots, principally poorly punched flash-holes - not properly centred, variable and over-sizing, and often misshapen / not properly round.

If you buy a quality make use straight out of the box is nearly possible - just chamfer the mouth inside (and in the case of Lapua which frequently has very tight necks from the factory, run cases over an expander ball or mandrel before priming and charging. Many of the cheaper makes have flash-holes though that are roughly punched leaving metal spikes (is there a proper technical term for such?) on the outlet side of the holes inside cases. A noticeable improvement can often be seen through use of a simple flash-hole debur / uniform hand tool - once-only job. All tool suppliers offer them these days - I use an ancient wood handle Lyman tool I've had for maybe 25 years.

If you get into custom built rifles for bench or long-range precision shooting, you'll learn there is brass and brass and usually a single, sometimes couple, of must-choose makes and that can just be a starting point for further modification / preparation. As you're on the AS Forum with 650 posts in, I'm sure you've already noticed the near tribal loyalty often exhibited for one case make or another though amongst top precision shooters.

Thanks Laurie, Yes my thought of going cheap on this plinker with brass was actually more work. I will use my close to end of life Lapua from my Panda F TR rifle. For the volume I shoot it wont be a problem having enough. I had about 100 of Hornady and Federal range brass. I'll toss that and use the Lapua with several firing on them. 100 or 200 will last quite awhile.

 

[Linko]

Reading all the great info in this thread, I believe the brass volume comparison would be:

1) Federal - most volume
2) Winchester
3) Lapua - least volume

Is that accurate?

 

[Laurie]

I bought two bags of 50 Hornady 6mm Rem cases, opened them, and chose the 50 best cases out of the hundred. Some were grossly malformed, others only dented or had striated necks/shoulders. I took the 50 culls back to Cabellas in on opened bag and got a full no-questions-asked refund there and then - no shipping anything back to an online source. This is a viable approach to buying economy brass,

Ha! Ha! Well done! I read a piece some years ago in the sadly gone German Salazar The Rifleman's Blog about a top 308 Win shooting sling shooter. He bought 1,000 Winchester loose cases at a time, scrapped the irreparably damaged ones and used the others as they came without any prep or batching. First firings would be in practice shoots or minor comps. If he got an inexplicable flier when he was happy with the shot and satisfied there was no wind explanation, he put that case back in the box mouth up (against his usual mouth-down practice) and marked the primer on the reload. If he got another poor shot out of it on the next firing it was tossed downrange as far as he could throw it to ensure it wasn't reused. This was most likely the 'banana case' syndrome where the case-walls are 0.004" or more thicker on one side than the other.

The Salazar feature was about this issue and went into some fascinating depth about Creighton Audette's work on this many years ago and the experiments he did indexing cases in the chamber. The still available NECO runout gauge is based on one Audette designed and made to measure case-wall thickness, and though most people now think of the NECO tool as a bullet runout checker, it'll still do the case-wall job as does the old RCBS Casemaster. Today's cases, even run of the mill ones rarely have too much trouble here, and the quality makes have very little variance in the walls at all - but back in the 1950s, there were apparently huge inconsistencies in wall thickness in some makes.

 

[Laurie]

Reading all the great info in this thread, I believe the brass volume comparison would be:

1) Federal - most volume
2) Winchester
3) Lapua - least volume

Is that accurate?

No. I would expect Federal to have the least capacity, at least in 308 Win on my experience. (However, I've not used this make for a long time in 308, so current production may have changed.)

The 2) and 3) order is definitely correct.

 

[Linko]

No. I would expect Federal to have the least capacity, at least in 308 Win on my experience. (However, I've not used this make for a long time in 308, so current production may have changed.)

The 2) and 3) order is definitely correct.

the reason for my interest is so in the future when comparing the load data between sierra and hodgdon manuals I have an idea when using Lapua brass

 

[Laurie]

Simple rule(s) of thumb, for:

1) Sierra (which usually uses Federal), Lapua and Peterson likely won't be much different.

2) Hodgdon and sources which use Winchester and Remington, reduce the quoted maximum by a full grain, 1.5gn if you want to be really cautious, for Lapua and Peterson brass in 308 size cartridges.

Remember that such data-sets should be treated as a guide and your rifle / brass (plus ideally a decent chronograph) tell you what is happening in your real-life situation. There is a lot of information about re excessive pressure signs, so read as much there as you can.

Here is a good illustrated article from the Primal Rights company's website showing progressive pressure effects on Hornady 6.5mm Creedmoor case-heads and primers

http://primalrights.com/library/articles/understanding-pressure

 

[Brians356]

I had a speer manual from the early 80's that I threw away cause the pages were falling out that had a 30-06 load 150 gr bullet at 3100 FPS I think with 4064 powder. I cant remember that many from there but that one stuck in my mind.

Speer Number Ten (1979) 30-06, 150-gr bullet, 22-in barrel:

H 205: 3059
I 4350: 2955
I 4064: 2941
I 3031: 2920
H 414: 2901

Speer #13 (1999) lists max only 2847 from that same 22" barrel (a full 200 fps slower!)

Sierra's manual lists max 3000 from a 26" barrel, Nosler 3056 from 24".
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[Laurie]

Speer #13 (1999) lists max only 2847 from that same 22" barrel (a full 200 fps slower!)

Manuals used to give test barrel MVs for their loads. Since these are specified at SAAMI or CIP dimensions, likewise the chamber reamer used, MVs were commonly higher than the load gave in a typical factory rifle with slacker bore and chamber and maybe considerably longer freebore.

That was OK until the peasants acquired chronographs and started to make ugly noises about being misled as their rifles failed to produce the expected velocities.

So, some bullet makers switched to a dual test regime - SAAMI rated pressure barrel to get the maximum load allowed for a combination, followed by some test shots in a real life honest to God Remington, Ruger or whatever, the make, model and barrel length quoted with the data-set in the components information. (Ammunition manufacturers faced the same problem as their older claims usually failed to be delivered in the punters' guns, not that any manufacturer would ever have been tempted to claim an extra 50 or 100 fps over what feasible of course to sell a few more cartridges ! )

 

[Brians356]

Manuals used to give test barrel MVs for their loads. Since these are specified at SAAMI or CIP dimensions, likewise the chamber reamer used, MVs were commonly higher than the load gave in a typical factory rifle with slacker bore and chamber and maybe considerably longer freebore.

That was OK until the peasants acquired chronographs and started to make ugly noises about being misled as their rifles failed to produce the expected velocities.

So, some bullet makers switched to a dual test regime - SAAMI rated pressure barrel to get the maximum load allowed for a combination, followed by some test shots in a real life honest to God Remington, Ruger or whatever, the make, model and barrel length quoted with the data-set in the components information. (Ammunition manufacturers faced the same problem as their older claims usually failed to be delivered in the punters' guns, not that any manufacturer would ever have been tempted to claim an extra 50 or 100 fps over what feasible of course to sell a few more cartridges ! )

I just notice Hodgdon lists a top velocity for 150-gr 30-06 at 3128 (24-in barrel) which is the highest I've seen in published data. But they also list the pressure at 59,600 psi. In Speer's very conservative data from 1999 (Speer #13) they state that pressure was limited to "industry standard 50,000 cup". So there you go, one explanation for 30-06 velocities being all over the map. I hadn't realized 50k was the SAAMI limit.

PS I know CUP figures run lower than equivalent PSI, but 59,600 psi is considerably higher pressure than 50k cup, which is probably about 55k psi.

PPS I see SAAMI max PSI for 30-06 is 60k. That doesn't necessarily mean 50k cup is equivalent to 60k psi, there is no conversion function. But it's not unlikely 60k psi is considerably "hotter" than 50k cup.
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[SPQR70AD]

I just notice Hodgdon lists a top velocity for 150-gr 30-06 at 3128 (24-in barrel) which is the highest I've seen in published data. But they also list the pressure at 59,600 psi. In Speer's very conservative data from 1999 (Speer #13) they state that pressure was limited to "industry standard 50,000 cup". So there you go, one explanation for 30-06 velocities being all over the map. I hadn't realized 50k was the SAAMI limit.

PS I know CUP figures run lower than equivalent PSI, but 59,600 psi is considerably higher pressure than 50k cup, which is probably about 55k psi.

PPS I see SAAMI max PSI for 30-06 is 60k. That doesn't necessarily mean 50k cup is equivalent to 60k psi, there is no conversion function. But it's not unlikely 60k psi is considerably "hotter" than 50k cup.
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how would you explain for the 30 Win short mag the top working PSI shown is 63600 PSI in the same rifle action? they said the low PSI for the 30-06 was for old rifles. I do not believe it. I think when they come out with a new round that does the same as established rounds they juice up the new round and throttle the old one. 30-06 was the king of the hill with 99% of hunters never needing nothing else and it had to be overcome

 

[Brians356]

how would you explain for the 30 Win short mag the top working PSI shown is 63600 PSI in the same rifle action? they said the low PSI for the 30-06 was for old rifles. I do not believe it. I think when they come out with a new round that does the same as established rounds they juice up the new round and throttle the old one. 30-06 was the king of the hill with 99% of hunters never needing nothing else and it had to be overcome

For newer cartridges for which they don't have to consider antiquated weak rifle actions, the pressure limit is determined by the brass case design in a modern action. A case with minimal body taper will produce lower bolt thrust. A case with thicker walls can handle more pressure. There are many variables in deciding where to set the limit.
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