Having a tough time finding R-P brass so I'm thinking about switching to lapua. All things being equal besides the brass how much could my load be affected?
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Having a tough time finding R-P brass so I'm thinking about switching to lapua. All things being equal besides the brass how much could my load be affected?
I would recommend backing down and working up again. Depending on the internal capacity of either brand of brass your pressures could go up or down.
Sounds like you already have a load worked up for the rifle so backing down and working back up shouldnt be an issue.
Scooter
Scooter said the phrase that pays.
"Internal Capacity". Don't confuse that with how much the brass weighs. Too many weigh, and expect that is a universality, it isn't; there is more than one formula to make cases from.
Personally I load by volume anyway, and honestly couldn't tell you when the last time I weighed a charge. That said I have some Norma, and about a handful of Lapua cases originally in 308. Honestly couldn't tell you if they are still 308, or if I squeezed them to 243, or cut down to 6.5 Creedmoor. I interchange brass without pause, but also don't typically run anything up at full pressure.
I'm not loading anywhere near max. I got lucky and found 100 once fired R-Ps so I may not have to find out just yet. May still buy 100 lapuas and do some testing tho.
why are you replacing the brass?
Getting loose primer pockets
For my pet load of 185gr berger vld hunting, 39gr of 3031, I would back off the say 36-37 gr and load 1 at each charge up .5gr level, up to my current load and check for pressure signs. If none, I would recheck accuracy at your preferred load and decide if you need to rework to find your node back.
This is what I would do for my load. 1 each at 36.5 37.0 37.5 38 38.5 39 39.5. If no pressure, 4-5 more at 39.0. If I needed to find my node again, I would go 38.2 38.6 39.0(already tested) 39.4 39.8. If I then had good between say 38.6 and 39, then you could split the difference to 38.8 and try it. Best case, 11-12rds to test, Worst case, another 20-25rds. You could trim a few shots off by loading only 3 or 4 rounds of each set.
..... Either you got soft brass, or in fact are well over Pressure.Quote:
Originally Posted by redwoood
Have you been trying to match a charge weight for "max"?
Velocity will tell you if you are over Pressure, not grains of powder.
Velocity is 2715 avg. Over my chrony. Only loading 42 grains imr4350.
What bullet are you using?
IMR4350 sounds a little slow to me for 308win.
I checked a couple of my books and hodgdons data and there is no listing for that powder under 308win(any bullet).
Edit.
Apologies, I see it was not you that mentioned 308win.
I second darkker's question below.
That looks like a Creedmoor load..... If so, you are well over max.
So what cartridge and bullet weight is this???
260 rem folks
And accubond 140s
I'm using the same powder on my 260. that load is moderate. I've had some issues with loose primer pockets on Nosler even with moderate loads
I know Lapua does well.
I personally have been using necked down 308 lc brass and haven't had any issues.
That load is also over max, using current Hodgdon data.
You matched their max velocity a grain before they hit that speed, and you are using a mass produced rifle; that is an over-Pressure load.
Published data sources mostly use SAAMI minimum spec: chambers, bores, grooves, throats. Mass produced rifles are nowhere near that tight, so will bleed-off more pressure. So even with the Same length barrel, a factory rifle should be slower at identical pressures.
You caught-up and matched max velocity a grain under, that should make all reloading cautions about "drop 10% when switching lots" very clear, that you have a much faster lot of powder.
Under max charge of powder, giving max velocities in a production rifle, AND stretching primer pockets.... those are clues my friend.
Stay safe out there.
I am fairly new to reloading and do not claim to be an expert.
According to my literature I am 1 grain under max. A quick look at hodgdon's website says 43 is max load.
http://www.hodgdonreloading.com/data/rifle
http://www.nosler.com/nosler-load-data/260-remington/
As for why I am getting 2715 with 1 less grain of powder out of my model 10 I have no clue. As far as the much faster lot of powder I probably should shoot over my chrony again soon since I only buy powder a pound at a time when I can find it. Just opened a new pound so that would be interesting to check.
You are running faster because of increased pressure, most likely due to burning rate. The more appropriate thing to focus on, to keep you from blowing through cases/equipment, is the velocity.Quote:
Originally Posted by redwoood
There are some faster barrels out there, but they are as common as hens teeth:cool:
Keep a close eye on your chronograph, and you'll have long lived cases.
Should I have mentioned I've reloaded this brass 4 or 5 times? Not sure what average brass life should be.
Only speaks to the pressures. I'm not into the "gotta anneal every 4 round" thing. Most of my 308 brass is well beyond the 30 reloads mark. My first batch of Creed brass is sitting about 20 reloads. Haven't had an issue yet.
As you reload/shoot more, you will find some brass is just a clinker after a couple reloads, but the junk usually fails quickly, the rest will live long lives if loaded in the design range.
how long is your barrel
have you cleaned the copper from the barrel at all since you've using it
24 inch barrel. I use a copper solvent every time I clean...butches I believe.
roger that redwood
Personally,id go necked down LC brass. I found it on (gunbroker)....... I purchased some horn. 140s as to fire form the brass and took it from there.
its 1/3 less the cost of nosler/lapua.
I still use nosler, but I prefer lc
Darkker ,,,,,,,,, i hate to sound stupid ,,, would you explain , when you reload you measure by volume,,,,, thanks for tolerating me
No sweat at all.Quote:
Originally Posted by savgebolt
Too many people in all industries, confuse a volume and weight. A volume is a displacement, with no solid ties to it's weight. A weight is simply somethings mass, regardless of how much displacement it takes up.
So when I reload, I measure powder in CC's but DO NOT re-check the weight; nor try and get "A weight", I need A volume.
A powder will ALWAYS have a varying BD(bulk density). This means that the amount of "power" potential in the powder will vary, when using identical weights of powder.
-Below is ONLY for Extruded powder!
Extruded powder has it's burning rate controlled by geometry(grain size, perforations, etc). The burning rate(geometry) is what controls how quickly that power potential is released. If you only weigh your charges, your volume, or case fill will constantly vary. Varying case fill will alter a powders burning rate. Only loading by weight will ignore the normal volume changes associated with differing BD's, so you get different actual burning rates. This potentially gets further aggrevated by the associated change in case fill.
If you are interested in this, Richard Lee's Modern Reloading manuals discusses this quite well.
thanx for the info , i will pursue that ,