Gunsmithing  POS Sako M995 or Pacnor Barrel

nuclabuyer

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I have a Sako M995 that has a 32" pacnor med palma barrel. I can not get it to shoot a single bullet with out 1 of 2 things happening. A. it is a delay fire, you hear the click and then a boom, or B. It is over pressure, like, way over. I started in the middle of the range with Retumbo and had to beat the bolt open with a hammer. So I went down to the starting load and click.... boom. Changed powder to RL 25, 102.2 click boom, 102.7, click boom 103.4 and way over pressure via heavy and shinny extractor marks and a flat primer. I sent it into Pacnor a year ago and they said it is good to go. I had them add a little free bore. I have been shooting other guns but I was hoping to use it for Elk season but that isnt going to happen.
I am using berger vld bullets, both 185 and 210. I have been back in forth between the 2 trying to get something to work. I bought a box of loaded ammo and high pressure there. Retumbo powder blows black soot all over the case after you shoot it. Dont notice it with any other powder. I cleaned it really really good and didnt help any. Any one have any ideas? I am tired of f#$%ing around with it. I am trying to decide if I should have chad cut me a new barrel for it, or sell it since I am going to have a 338 edge in January or February.
 

nuclabuyer

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Re: POS Sako M995 or Pacnor Barrel

Out of everything I forgot, I forgot that. I am shooting a
30-378 weatherby
 

BradfromND

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Re: POS Sako M995 or Pacnor Barrel

If you want to give away that POS 995 action and stock, I'll take it off your hands. I highly doubt that is the problem but I could be wrong. Those are incredible actions but, I guess, occasionally there are mistakes. I'd send it to a smith and let them check it out.
 

Straight Shooter

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Re: POS Sako M995 or Pacnor Barrel

Federal 215's are a must with this large case. You don't want to go below starting charges or you could get what is known as a detonation of your powder rather than a controlled burn. Detonations from too light of charges will go off like a super max load.

CCI-250's will work in warmer weather or with faster powder.
 

nuclabuyer

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Re: POS Sako M995 or Pacnor Barrel

I am using a CCI Magnum primer. Do you think the Fed will change it that much?
I go as far down as min load, example being my lyman book says 101-106 is the range for a 185 and RL-25. I made it to 102.2gr was delay fire and the 103.4 was over pressure. I have never used anything beside CCI for large rifle. I will get some Fed primers if the cup is thinker and will hold a little more pressure.
 

Straight Shooter

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Re: POS Sako M995 or Pacnor Barrel

Yes the Fed 215 will get rid of the hang fires. I doubt the cup is any thicker. I am a huge fan of the CCI-250 to the tune of no less than 10,000 on hand at all times. They just have their limitations and light charges in big cases is it. I use them in everything from 22-250 to 300Wby with no trouble. 300 RUM on up is where the trouble starts. I run them fine in my 338 Lapua but I haven't tried them below 60 degrees in the Lapua . If I did I would expect some hang fires.
 

hero's machine

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Re: POS Sako M995 or Pacnor Barrel

Primer issue is my first guess. I have had a few rounds of brass that were odd and caused a similar over pressure with what should be safe charges. I would check water capacity on the case if a gm215 won't fix it.
 

the gman

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Re: POS Sako M995 or Pacnor Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hired Gun</div><div class="ubbcode-body">What do you base this on? The primer issue is a known issue. What symtoms are we missing that would indicate a bad chamber? I would bet a nickle that chamber is within go, no go gauge specs. </div></div>

Then how would you explain the OP having over pressure issues with FACTORY ammo? Not trying to be argumentative but your solution of primers doesn't seem to make any sense to me. Hang fires maybe but the over pressure issues within a grain or two of the starting load and the same over pressure issues with factory ammo screams chamber problems to me. I would want PacNor to prove to me the barrel/chamber was GTG or change the barrel.
 

Straight Shooter

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Re: POS Sako M995 or Pacnor Barrel

No arguments needed. Let's think this out.

Here is my thought process on what we know so far.

<span style="color: #3333FF">I have a Sako M995 that has a 32" pacnor med palma barrel. I can not get it to shoot a single bullet with out 1 of 2 things happening.

A. it is a delay fire, you hear the click and then a boom,
The causes for hang fire can be related to the firearm or the ammunition. Light firing-pin strikes or weak primers not initiating proper ignition. </span>
Too slow of powder. Not enough powder. I have history with a couple RUMs that required a fed 215 to get rid hang fires especially with slower powders like US869 and RL25.

<span style="color: #3333FF">B. It is over pressure, like, way over. I started in the middle of the range with Retumbo and had to beat the bolt open with a hammer. So I went down to the starting load and click.... boom. Changed powder to RL 25, 102.2 click boom, 102.7, click boom 103.4 and way over pressure via heavy and shinny extractor marks and a flat primer. </span>

To beat the bolt open can be caused from high pressure or soft brass. Weatherby brass is built by Norma and it is known to be extra soft. Factory ammo is known to be loaded fairly hot and extractor marks are the normal. In belted mag cases. Even with normal pressure the case just above the belt grows slightly with every firing and cannot be resized with normal full length dies. Eventually this will stick so bad you either use a mallet or the extractor will jump the rim and you will have to use a ramrod to extract the case. My 300Wby does this at around 10-15 firings. When I feel those cases getting sticky it's time to dump them.

<span style="color: #3333FF">I sent it into Pacnor a year ago and they said it is good to go. I had them add a little free bore.</span>

PacNor most likely did as any gunsmith would and double checked the head space with a set of gauges and it must have passed the test. They also have borescopes everywhere ( I have been there) so I would be sure the chamber was visually checked as well. The complaint department is KC. This is the owners son so the accountability is there. No risk of an hourly rate guy trying to skate on you.

<span style="color: #3333FF">I bought a box of loaded ammo and high pressure there.</span> See answer to B. This one puzzles me and the only thing that comes to mind is if the free bore is over spec it will cause a low pressure that will cause an incomplete burn and be really dirty running. Low pressure is what causes soot on the cases and inefficient powder burning. What was the velocity?

<span style="color: #3333FF">Retumbo powder blows black soot all over the case after you shoot it. Don’t notice it with any other powder.</span>
Soot or unburned powder is cause by incomplete burning. Low pressure from not enough powder or weak ignition can cause this. What is happening is the case neck doesn't have enough pressure to form a good seal on the neck allows the soot to blow back around the cases and will lead to very sticky extraction.

What's really missing here is chronograph data. High pressure usually show high velocity. The increasing powder charges should show a linear increase in velocity. If not we know we may have some detonation going on.
 

shoot4fun

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    Re: POS Sako M995 or Pacnor Barrel

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hired Gun</div><div class="ubbcode-body">What do you base this on? The primer issue is a known issue. What symtoms are we missing that would indicate a bad chamber? I would bet a nickle that chamber is within go, no go gauge specs. </div></div>

    You are probably correct. I've had work done by PacNor before and they are first class. Sorry I got a little ahead of things.

    To the OP, have you tried shooting any factory ammo thru the rifle?
    If so, what happened?
     

    nuclabuyer

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    Re: POS Sako M995 or Pacnor Barrel

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nuclabuyer</div><div class="ubbcode-body"> ... I bought a box of loaded ammo and high pressure there. </div></div>

    I did notice that there was high pressure on the loaded factory ammo. However after thinking about it, I would say that if I were to compare the factory loaded and fired case and the reloaded fired case, that the factory case showed less pressure even though I am certain that the factory reload is loaded way hotter. I would say that the primer was flat and was cratered some, but certainly didnt need beat open. So maybe after all this, it is nothing more then just a primer problem.
    I did buy a new batch of Nosler Custom brass, all the previous brass was the weatherby brass but the Nosler has an over run and is marked down from 77 to 50 for 25 pieces, so I bought some. Now I need to get me some Federal Primers. And test it out. Thanks to everyone.
    I have learned alot. I had no idea about the Federal primers being better for high cap loads.
     

    shoot4fun

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  • Oct 27, 2003
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    Re: POS Sako M995 or Pacnor Barrel

    I use CCI small rifle magnums in 6BR with great results but I only use FGMM magnum primers. Frankly, I never realized there were issues with the CCI is heavy loads.
     

    nuclabuyer

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    Re: POS Sako M995 or Pacnor Barrel

    I also didnt realize that a CCI mag primer was a little weak for this kind of case and powder volume. I would like to thank everyone for the conversation that took place. I ordered new brass and hopefully I will get some Federal 215's and I will try and see what we get. Again, this has been very informative

    thanks