Your thoughts

pointy sticks

Well-Known Member
Joined
May 5, 2020
Messages
245
Location
Washington State
300 win
h1000
22in carbon six
Suppressed
Berger 205
2.907 CBTO
10tho off lands
Fed 215 m
New ADG

73. 2755
73.5 2700
74. 2700
74.5 2749
75. 2815
75.5 2807
76. 2798
76.5 2855
77. 2878
77.5 2911
78 2906
78.5 2936
79. 2959
79.5 2976
80. 3009
80.5 3026
81. 3044

Cases shown last 3 fired on the left is 80 middle is 80.5 on right is 81g.
Wondering if I should keep going I was only expecting 2900fps range with this short of a barrel.

Thanks
 

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To adequately discover pressure, you'll need to be putting multiple firings on a single case. There's certainly some pressure there, but the virgin firing will mask pressure due to the brass absorbing and flattening out the pressure spike as it expands to fill the chamber. This is especially common with belted cases, as their shoulder is not where headspace is set, and most brass will be looking at a 10 thousandths or so secondary headspace difference to the shoulder on a fired case. More so by the 3rd firing. This is also why novice handloaders can often struggle to get the same kind of accuracy out of subsequent firings as they can the virgin firing. That first firing generally is very forgiving, as it elongates the time on the pressure spike. (a clue for those only neck sizing)

Secondly, you'll want to be doing this work on a well seasoned bore. At least 100rnds deep on a 300WM. Fresh bores can mask pressure as well until they foul in a bit.

Use a single case, reload it at the higher end of pressure (80 is definitely high) until it produces heavy bolt lift. That will give you some basic indication of when its experiencing plastic deformation and being pushed out of its elastic capabilities.

I would agree with you in that those velocities are significantly beyond what is normally seen in that barrel length. Proceed with care.


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Thanks for your in put! @orkan Ya shoulder stretched right at 21tho. I was a little worried going to 80 but didn't experience pressure signs I am used to seeing. This is my first time trying ADG so I wasn't sure if that was normal. I know the nosler I normally use would have had ejector marks on it by about 78g.


Edited fat fingers put 12tho in stead of 21tho.
 
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Thanks for your in put! Ya shoulder stretched right at 12tho. I was a little worried going to 80 but didn't experience pressure signs I am used to seeing. This is my first time trying ADG so I wasn't sure if that was normal. I know the nosler I normally use would have had ejector marks on it by about 78g.
ADG tends to mask pressure early, but you'll want to stay lower on the pressure. Just because it can take it without necessarily showing it, you'll start to see cases separate from the batch every firing as a result of non-uniform plastic deformation. Most guys are dumping their brass in the trash after 5-6 firings... if even that. So it's generally not an issue for them, and as that's the bulk of the expectation... it isn't spoken of much. I'm generally seeing 60-100 firings on most cartridges, but I also use different brass to achieve that. Most brass makers aren't able to make brass that can maintain accuracy across that many firings. Generally not even close.

So what I'm saying is, keep an eye on it across your firings to ensure you're not seeing flyers show up due to case uniformity degradation on subsequent firings.

I go into some of this in detail in these videos:





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Last edited:
ADG tends to mask pressure early, but you'll want to stay lower on the pressure. Just because it can take it without necessarily showing it, you'll start to see cases separate from the batch every firing as a result of non-uniform plastic deformation. Most guys are dumping their brass in the trash after 5-6 firings... if even that. So it's generally not an issue for them, and as that's the bulk of the expectation... it isn't spoken of much. I'm generally seeing 60-100 firings on most cartridges, but I also use different brass to achieve that. Most brass makers aren't able to make brass that can maintain accuracy across that many firings. Generally not even close.

So what I'm saying is, keep an eye on it across your firings to ensure you're not seeing flyers show up due to case uniformity degradation on subsequent firings.


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Ya I usually run a lower node but like to know where pressure is. My last batch of 300wm had around 20 firings on them. What brass do you prefer to use for belted mags?
 
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Looks like you have a node right around 2900 FPS and if it were me I'd play around with that. 22" barrel I'd be plenty happy with that velocity. RL26 would probably get you more.
 
Seems like really good velocity for a short barrel. What is the bearing surface on the 205 ? The 215 bearing surface is short compared to the 210 VLD and the 215 gives higher velocity for this reason and sounds like the 205 might run fast for the same reason. If you want to run a lower node it looks like the 77.5 & 80.0 has a flat spot in velocity. The ADG is super tough and probably won't show signs of pressure so keep on eye on the primers. Do the lower charges look the same as the top end ?
When I start a rifle up I fire all 100 of my brass with the bullet jammed so the brass will form to the chamber with the case head against the bolt allowing the shoulder to get maximum expansion.
Either way it sounds like you have a great rifle !
 
Seems like really good velocity for a short barrel. What is the bearing surface on the 205 ? The 215 bearing surface is short compared to the 210 VLD and the 215 gives higher velocity for this reason and sounds like the 205 might run fast for the same reason. If you want to run a lower node it looks like the 77.5 & 80.0 has a flat spot in velocity. The ADG is super tough and probably won't show signs of pressure so keep on eye on the primers. Do the lower charges look the same as the top end ?
When I start a rifle up I fire all 100 of my brass with the bullet jammed so the brass will form to the chamber with the case head against the bolt allowing the shoulder to get maximum expansion.
Either way it sounds like you have a great rifle !

@Wedgy

Do the lower charges look the same as the top end?
In what way? the way the brass looks?
On the lower end I had a few primers sticking proud of the case head and some soot on the necks.
Thanks for all the feed back fellas! ya seems like it's a quick barrel.
 
Looks like you have a node right around 2900 FPS and if it were me I'd play around with that. 22" barrel I'd be plenty happy with that velocity. RL26 would probably get you more.

Ya I think I will just mess around there that's all I was expecting any how. But I would hate to leave 100fps on the table if it's there with no pressure. 😉
 
If it were me, I'd be looking more at SD/ES and grouping than absolute maximum velocity. Especially with my thinner profile barrel contours, I often find that loading down from max pressure helps with group size and consistency.
As mentioned above, if your brass and barrel aren't well broken in, it can all be subject to change anyway.
 
If it were me, I'd be looking more at SD/ES and grouping than absolute maximum velocity. Especially with my thinner profile barrel contours, I often find that loading down from max pressure helps with group size and consistency.
As mentioned above, if your brass and barrel aren't well broken in, it can all be subject to change anyway.

Ya your right I will be getting to that. I was just wanting to find pressure so I knew where it was and was expecting to hit it way earlier then 81g.
 
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