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Apparent over pressure from mild load

straightshooter1
BongEyes said:
G'day all

Im scratching my head on this one. Need some assistance.

Running a 6.5 PRC
28" Custom barrel SAAMI Chamber (.533 web)
on tikka t3 action.

153.5 Berger Hybrid Target
ADI 2217 (H1000) at 50.5grn (4.5grn below book max)
Surplus Indian Army LRP
Norma Brass trimmed to 2.015"
Loaded neck OD = .2935
Shoulder bumped back 0.002" after full length resize using SAC bushing die and mandrel
COAL 3.05"
Approx 25 thou jump to lands
Case capacity measured to 70.5grn h20

Velocity measured to 2915fps via Xero chrono which is super fast at this charge weight according to the book...
Using GRT this load is showing a pretty mild pressure curve...and certainly well below max


But, I have been getting excessive pressure signs; from the minimum charge upto 52.5grn
Heavy bolt lift/clickers
Cratered primers
Blown primer x2 once with a stuck case and torn rim from extractor claw
Ejector swipes
Primer pockets lose/unuseable after 2 firings on some pieces of brass.

Before you crucify me for running over pressure I have tried 2 different bullets and 2 different powders starting low and working higher. All showing signs of OP. 50.5grn has been fairly stable except for the clickers.

Really the only other variable to change is the brass (I've heard Norma can be very hit/miss on its QC and often produces soft brass) and I am heavily leaning towards this as the problem I am facing and wondering if anyone else thinks could be the issue...
However it dosnt explain the vast increase in velocity I am recording compared to what the book is saying...

Any insight on wtf is going wrong with this would be helpful. I have thought of everything I know and will be first to admit I don't know everything.
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You said your "GRT is showing a pretty mild pressure curve" and so does my QL app. In fact, the curve is VERY low. While you say you're at "minimum charge up to 53.5 gr", that "minimum is based on who's reported minimum charge and case volume? Norma case volumes are 3-4 grs more in volume than other brands, so you could be well below recommended minimum case charge??? And, as I look at the powder charge of 50.5 grs ADI 2217 in my QL app, it's showing the case filled to only 85.5% (given your reported case volume). Case fill that low would give me concern for high pressure spikes, which is known to happen with a very low case fill. This may not be "THE" factor going on, but I have a feeling it's contributing a lot to it.

For my 153.5's in my PRC, I've never used H1000 or ADI AR 2217. I like to run 57.5 gr N565 behind 153.5's producing 2,980 fps out of a 26" barrel. But I've often seen reports for charges of ~57 grs of H1000 producing around 2900 fps. That why what you're reporting is a little shocking to me. My QL app shows a 50.5 grs of ADI AR 2217 produce ~ 2500 fps and ~50 fps more with case volumes reduced to what I get with my thicker case wall Lapua brass. I just can't imagine 400 fps difference that you're getting without something causing an unusually high pressure spike.
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India vs Pakistan

L
mosin46 said:
yea,Indians are always GTG to kill Muslims. not a bad thing really. how would the Buddhists and Catholics fare? what might be the effect in this country,ESP universities and containing cities? eg Gainseville,FL. and UF are over run with dot heads and rag heads. maybe some hot action like Palestinian and Jewish disorder all over the university world. of course you got the huge #s of PLA spies throughout academia but don't think they would join in.
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Christians are being persecuted in India severely- beaten and killed, churches being torn down with little to no police action.

Buddhists are catching it hard too, but there is real animosity between the Muslims and Buddhists. Don’t believe everything you hear about Buddhists being super peaceful- there was a genocide on the Rohingya group in Myanmar and the Indian Mujahadeen went all FAFO and blew up part of the Bodh Gaya in Bihar (state in India). Then they did it when the Dali Lama was there after that, and that was the JMB out of Bangladesh. There are so many groups like that inside of India it’s hard to keep track of them all. They are only contributing to India’s lack of patience with the Paks.

To answer your question on universities, who knows. I have worked stateside with both Bangladeshis and Indians on the same teams. They work together OK, but they aint breaking bread after hours. I can say that I have never seen people treat each other as poorly as Indians do to each other.
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Maggie’s The Welding and Metalworking Thread

sirhrmechanic
A couple of years ago, before heading to Labrador, I made a foot for my Dakar kick stand. Because it always was way too small and on dirt would sink in. The only times I ever 'dumped' the bike was kickstand crap.

But my 'new' foot (which was a smooth piece of aluminum) didn't do 'great' in part because the bolt heads were sticking up (fine no dirt.. not so good on pavement.) And I still wanted more 'height' to keep the bike more upright.

So made up a new foot. Based on Bipod claw designs. Stainless, not aluminum.

1746041053905.png



This won't slip on anything! Stainless foot with sharp claws. I will probably leave footprints on asphalt from coast to coast! Will have the added benefit of keeping the bike more 'upright' as the original Dakar kickstand lays the bike 'way' too far over.

Going to have some fun painting it up, too. Why not?

Maybe I can park my bike on top of an ANTIFA or some kind of commie troll.

Cheers,

Sirhr
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India vs Pakistan

M
yea,Indians are always GTG to kill Muslims. not a bad thing really. how would the Buddhists and Catholics fare? what might be the effect in this country,ESP universities and containing cities? eg Gainseville,FL. and UF are over run with dot heads and rag heads. maybe some hot action like Palestinian and Jewish disorder all over the university world. of course you got the huge #s of PLA spies throughout academia but don't think they would join in.
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PVA now offering AR15 barrels!

bohem
We just finished up a batch of AR barrels (I apologize for how long it took us)

We have 223 Wyldes in the usual 16/18/20 and we added 16" with Intermediate length gas (using the Noveske spec IM). I didn't make a ton of those so we could see how they would sell, but we do have about 2 dozen available currently.

223 Wylde
22 ARC
6mm ARC
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PortaJohn

M
theLBC said:
posted this yesterday (different source) but i have to wonder what is the patriot act for again?

www.usatoday.com

Suspected ISIS member arrested in connection with New Orleans attack, Iraq says

The unidentified suspect is believed to be affiliated with the Islamic State militant group, according to Iraq's Supreme Judicial Council.
www.usatoday.com
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it is to exercise tight control over rt leaning US citizens,white if possible. and yes,Christians very much so. need to control those terrorists who care what their children are being exposed to in gov indoctrination centers.
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India vs Pakistan

L
LeT is supported by the ISI. The Indians have known this for a LONG time but the indopak border is porous as hell. India’s got all kinds of internal problems, including the Maoists that never have been eradicated. Those fuckers will set up machine shops in the middle of jungles to make weapons and IEDs. Every time I was there no fewer than 5 Muslim extremist groups were active in my area, plus the Naxalites. All that to say that if this goes hot I expect that there are a lot of Islamic groups that will create even more chaos inside of India. All this will do in the short term is cause local Indians to kill Muslims and increase the Indians allegiance to the BJP and its India First goals. The RSS will come out in force to promote this, and all non-Hindus and non-Sikhs will suffer for it. If it continues into the Puja season, holy shit.
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Best AR-15/M16 Bolt Carrier Group For The Money…Who Ya Got??

N_Turs
WeR0206 said:
I’ll def be adding BCA to my list. I don’t have any experience with them but only hear great things. I do have a headspaced BCA bolt coming with my Osprey barrel that I should hopefully have on hand within a few weeks.
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I run one of their light weight Ti carries in a match rifle I have and its pretty awesome. Run it with a jp bolt and unrivaled buffer set up. Shoots amazing flat.
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