That’s a very informative post, thanks
GRT - What Am I Doing Wrong?
- Thread starter Dr. Strangelove
- Start date
Thank you both for your replies.
I do realise it is an approximation, and that there is a potential for error between the actual bullet and the bullet Library. There presumably will also be a slight discrepancy deriving from the fact that due to springback the fired case is still smaller than the volume in the case that is expanding towards the chamber wall before the bullet starts to move.
The volume difference between brands and batches of cases and the chambers they have expanded into, is also going to be fairly small, around 1gr but apparently worth our measuring with water as it is specific to our rifle and our brass.
In the wee small hours of the morning I was just interested to know whether the primer void was accounted for within P-MAX because it is fairly consistent at around 0.5gr, depending on cup wall and anvil size and is thus a predictable rather than a potential error in calculating.
Hence my query.
Thank you both again
Alan
Understood - I was using the RS temperature coefficient data here - Reload Swiss temperature coefficient. Unless I'm wrong, and I could be, that '0.25ms pro K' figure equates to 0.82fps per degree Celcius. Or about a 24.6fps change for a 30deg C swing in temp. The data they posted is for 8x68 S but I figured it might extrapolate across irrespective of cartridge. With the '0.55ms pro K' data, that equates (I think) to around a 54fps swing over 30deg C. Not massive!
Thanks, I've found a good load for D073.6 with 77gr SMKs in a 5.56x45 so may have a play with it in 308.
If you are willing to go a bit softer on velocity and do a bit more dialing for elevation, my pal who is a meticulous reloading wizard obtains exceptional accuracy and consistency in his .308 SIG using 40.3gr of N150 with 190gr SMKs. He lets me shoot the SIG sometimes and it works for me too.
Attachments
When Nigel, of Commonside, introduced RS powders to we target shooters, very professionally, he chose RS50 and RS60.
Which he branded as TR140 and Elcho17. By analogy with Vhit. N140, and Reloder17. RS50 is very similar to N140. RS60 is of course exactly the same thing as Reloder 17. Staples of many target shooters. Half the price, at the time, when I used to buy it at e.g. the Phoenix meeting (I think he is very local to Bisley).
Nowadays he is the importer of the full RS range, which has gone from strength to strength. And RS have, I believe, worked closely with the QuickLoad man, to match closely. Indeed they provide a library of their own, to download and import into QL. I have had a little dialogue with them too, they are very responsive and educated.
Around the same time another very nice chap, trading as Westlander, introduced the Explosia/Lovex range to the UK. I didn't latch on to that at the time, but nowadays of course it is quite a thing. I did buy my gun safe from him though. I've lost touch with whether he is still the conduit for Lovex into GB, I do hope so, certainly he is still trading (and selling Czech made gun safes, which are good).
second time around with better light and jeweller's loupe for a more precise water level
302mg dry 334mg wet with anvil....32mg / 0.494gr
218mg dry 256mg slight crown wet without anvil....38mg/0.586gr
Alan
BTW, I have an idea about your 100 mg difference between my estimations, and your measurements. It's to do with the protrusion of the anvil on the unfired primers (which you can see sketched on the SAAMI drawings) When properly seated, the protruding anvil should be pushed back until flush with the rest, "setting" the priming compound. Here is a an idea, measure the length of the primer before seating, then after it has been properly done, squishing the anvil flush. That might account for the discrepancy.
Even more fun, weigh a primer, before and after firing. The difference will be the mass of the the priming compound. Usually lead styphnate, but other green things are already in use, and may become ubiquitous. Sorry, but even proper milligram scales (start at £400) aren't going to be good enough. You would need an analytical grade one (0.1 mg), start at £1000, to detect the differences. Plus, of course a proper calibration weight as well (not a check weight). These are not cheap.
AFAIK, nobody has delved deep into this, yet, I think. It's all too empirical for me. But this is not my day job, nor have I much interest in the niceties of which primers are best, most consistent, the difference between ordinary, magnum, bench rest etc. Brands, country of origin, consistency and so on. Esoteric large cases but with small primers. Flash hole diameters different from the norm. I think @Laurie is, however.
What do the simulators have to say about this ? Very little I suspect.
Even more fun, weigh a primer, before and after firing. The difference will be the mass of the the priming compound. Usually lead styphnate, but other green things are already in use, and may become ubiquitous. Sorry, but even proper milligram scales (start at £400) aren't going to be good enough. You would need an analytical grade one (0.1 mg), start at £1000, to detect the differences. Plus, of course a proper calibration weight as well (not a check weight). These are not cheap.
AFAIK, nobody has delved deep into this, yet, I think. It's all too empirical for me. But this is not my day job, nor have I much interest in the niceties of which primers are best, most consistent, the difference between ordinary, magnum, bench rest etc. Brands, country of origin, consistency and so on. Esoteric large cases but with small primers. Flash hole diameters different from the norm. I think @Laurie is, however.
What do the simulators have to say about this ? Very little I suspect.
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I have found this powder to be very versatile. Like you, I have used it in 223. Also in 204 Ruger, 6.5 Grendel (where it remains top performer in my CZ's), 7mm-08, and 308. When it was silly cheap ($130 / 8 lb keg) I bought four of them. I have about 26 pounds of it remaining and eagerly await my shot at finding some more. (Should that ever happen) ~Muir
How about £12.00 from the Beaulieu Autojumble in C 1977? I spotted the glass and mahogany case behind the stall and thought it would make a good showcase for my jewellery, Asked the guy how much and he said £15 as he lifted it up on to the table...I saw that it was this beautiful set of Agate knife and plane, air damped Oertling Brass Lab scales and was gobsmacked...he interpreted my silence as a bargaining ploy and dropped unasked to £12? I waited bit longer but he didn't go any lower!
You can easily spot the difference between large, medium and small kernels of N135.
Alan
Before we were upgraded to optical I used to download big files over the 4g system and/or overnight by tethering the PowerBook to the iPhone which was 10x faster than the copper landline broadband. We have only been on optical for a couple of years, but it is amazing how quickly I have lost the worry about large downloads.
Go round to a chum’s house for a coffee and a download rather than a doughnut?
Would be interesting to hear your take on it.
Alan
In podunk Montana you get what you get for internet service. Every time the weather changes (for good or bad) my internet goes out. I wanted to see it out of curiosity. Had Quick Load many years back but it never told me anything I couldn't deduce from experience or practice.
What I am amazed at -and I mean dumbfounded- is that people that load 2 or 3 standard chamberings will go through the hassle of all the measurements when standard manufacturers load data is available. At last count, I load / loaded for over 110 different cartridges, much through the pre computer ages. How did I manage?
I may download GRT yet..... Winter came back for a visit. I need to cast some .520 round balls before the next snow. Maybe I'll let it run while I do. ~Muir
What I am amazed at -and I mean dumbfounded- is that people that load 2 or 3 standard chamberings will go through the hassle of all the measurements when standard manufacturers load data is available. At last count, I load / loaded for over 110 different cartridges, much through the pre computer ages. How did I manage?
I may download GRT yet..... Winter came back for a visit. I need to cast some .520 round balls before the next snow. Maybe I'll let it run while I do. ~Muir
It is about a 250 Mbyte download. Just tried it again, the 2048 expiry GRT 2021.2030.NIGHTLY (public) last (so far) version. Took under ten seconds (but I am blessed with fast internet).
I agree with your consternation, but there again some people just want everything for free. And are not particularly keen on reading/studying. Or even sufficiently numerate to understand what they are using. I mean a proper reloading manual isn't cheap these days, from the sort who do the expensive work to actually independently test powders and bullets in test equipment, then sell it as hard copy I think you know a little about that. You won't find that depth of information for free on their websites, except for a potted summary.
There seems to be a fascination with tinkering with such things, understandable when actually getting out and shooting takes more effort, preparation, equipment and time. Not to mention the cost. Fair does, I am guilty of that myself.
There is even one chap on here who claims to be keen to have the latest Quick Load, has the money for it (maybe a full set of the latest good reloading manuals, or 1.5 kilos of powder equivalent) but has come up with some fatuous excuse that, if he can't just download it he can't be a@rrsed. Ahem, it only comes on physical media, a CD or whatever. But no, that's too much trouble for him, doesn't have an optical drive, never will, because he is a 21st century man living in 2022. I've even offered him a way around that, but no response, and he's gone a bit quiet since then. Ahh well.
Praise the Lord and Load (not pass) the Ammunition, as I daresay might be an addendum to the Hodgdon mission statement. God and mammon.
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Excellent assessment. Thanks.
I did manage to download GRT just now. Four Minutes. Somebody must have shooed the crows off the telegraph wires.
So I looked at the manual: 137 pages of condensed reading. There are a lot of good reloading books with less reading than that! Must be the techy aspect that draws people.
I will begin to digest the manual as time allows. I look forward to it.
Thanks for the encouragement.
~Muir
I did manage to download GRT just now. Four Minutes. Somebody must have shooed the crows off the telegraph wires.
So I looked at the manual: 137 pages of condensed reading. There are a lot of good reloading books with less reading than that! Must be the techy aspect that draws people.
I will begin to digest the manual as time allows. I look forward to it.
Thanks for the encouragement.
~Muir
Actually, I did order it from Julian, but cancelled the order when I found out how archaic it was and then found GRT, which is modern software that works well. Sorry, I didn't respond immediately to your idiotic non-solution but I was out having a great day in beautiful weather at Bisley. I think it probably best we ignore each other from now on, I've certainly pressed the ignore button on you, you witter on fatuously pointing to other people's work without adding anything useful yourself or it appears doing any shooting. As far as I know QL woks well but if it is not available in a format I can use, then I'm not jumping through hoops to use it. I will also not be taking up your kind offer for me to buy QL for you to then send me a pirated copy, while you keep the original.
Genuine question, if this is an issue, then wouldn't the simplest solution be to decap , then use a spent primer , level filled with modelling clay for example , seated in its place before beginning the whole process ? Or even seat a spent primer inverted in its place ?
There is, of course, a solution to this "problem". Could be handy if you want to measure a whole batch of brass and sort by volume. Though I suspect that simply sorting the cases by dry weight would be good enough. But you'll never know until you have tried:
https://21stcenturyinnovation.com/buy-online/ols/products/primer-pocket-plugs
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