I'm using Lapua Palma small rifle primer 308win brass. I was wondering if using small rifle primers have any effect on the pressure curve or overall chamber pressure?
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Re: Does using Palma brass alter chamber pressure?
I love the Palma brass, I have some with 10+ firings and primer pocket is still tight. I found I had to add .2 gr of powder to get the same speed as the reg brass. Other than that you can definitely load a slightly hotter load with no primer issues.
I love the Palma brass, I have some with 10+ firings and primer pocket is still tight. I found I had to add .2 gr of powder to get the same speed as the reg brass. Other than that you can definitely load a slightly hotter load with no primer issues.
Re: Does using Palma brass alter chamber pressure?
MALLARD, I didn't think their was a huge difference, but Ive heard some people say it's a little less pressure and some say it's a little more. At this point all I can do is come up with my own theory. Maybe someone with greater skills and equipment than myself has measured this somehow.
EROCO, Sounds like it's slightly less from your experience. This is what I suspected, but had nothing to base it on.
I also love my Palma brass. Have 25+ firings and no primer pocket issues. Plus, I tend to shoot them a little hot
. My only concern is that I seem to never get flat primers. I guess it's too hard to flatten them. Checking the primers for pressure signs is useless. My 1st sign of pressure is marks on the brass.
Thank you both for your imput.
MALLARD, I didn't think their was a huge difference, but Ive heard some people say it's a little less pressure and some say it's a little more. At this point all I can do is come up with my own theory. Maybe someone with greater skills and equipment than myself has measured this somehow.
EROCO, Sounds like it's slightly less from your experience. This is what I suspected, but had nothing to base it on.
I also love my Palma brass. Have 25+ firings and no primer pocket issues. Plus, I tend to shoot them a little hot
. My only concern is that I seem to never get flat primers. I guess it's too hard to flatten them. Checking the primers for pressure signs is useless. My 1st sign of pressure is marks on the brass. Thank you both for your imput.
Re: Does using Palma brass alter chamber pressure?
The small primers seem to handle high pressure a little better. It takes longer for the primer pockets to get loose.
That just disguises pressure, though. Overpressure is overpressure. Tough on the action, tough on throats, and little margin for safety.
The small primers seem to handle high pressure a little better. It takes longer for the primer pockets to get loose.
That just disguises pressure, though. Overpressure is overpressure. Tough on the action, tough on throats, and little margin for safety.
Re: Does using Palma brass alter chamber pressure?
I agree. I've been reading posts on the Hide now for a couple of years before recently registering. I've always seen that flattened primers were an early sign of over pressure. Fortunately, I never really pushed the limits because this obviously doesn't apply to Palma brass which was unknown to me when I started.
Thank you for your imput Carter. After hundreds of hours of using the Snipers Hide Search Engine over the last 2 years i've seen your name countless times. Nice to meet you.
I agree. I've been reading posts on the Hide now for a couple of years before recently registering. I've always seen that flattened primers were an early sign of over pressure. Fortunately, I never really pushed the limits because this obviously doesn't apply to Palma brass which was unknown to me when I started.
Thank you for your imput Carter. After hundreds of hours of using the Snipers Hide Search Engine over the last 2 years i've seen your name countless times. Nice to meet you.
Re: Does using Palma brass alter chamber pressure?
Nice input folks. The small primer does indeed make the pressure signs go elsewhere. I know when I'm close to max pressure the bolt lift gets a little tougher and my Win small rifle primer gets punched through. My melonited barrel after 850 rounds though shows no throat erosion or heat cracks
Nice input folks. The small primer does indeed make the pressure signs go elsewhere. I know when I'm close to max pressure the bolt lift gets a little tougher and my Win small rifle primer gets punched through. My melonited barrel after 850 rounds though shows no throat erosion or heat cracks
Re: Does using Palma brass alter chamber pressure?
I'm glad you shared that bit about your primers getting punched through. I have been using cci br4 primers because of their cup thickness. Nice to know that my caution was warranted. Since small rifle primers are not as thick as their larger cousins I wanted to get the thickest non magnum primer available. This link has that info on primer thickness if your interested. The one they do not show is the cci #41 small rifle military primer. It is the same thickness as the br4, but a magnum and it has shorter dimensions to avoid a slam fire in autos.
http://www.jamescalhoon.com/primers_and_pressure.php
I'm glad you shared that bit about your primers getting punched through. I have been using cci br4 primers because of their cup thickness. Nice to know that my caution was warranted. Since small rifle primers are not as thick as their larger cousins I wanted to get the thickest non magnum primer available. This link has that info on primer thickness if your interested. The one they do not show is the cci #41 small rifle military primer. It is the same thickness as the br4, but a magnum and it has shorter dimensions to avoid a slam fire in autos.
http://www.jamescalhoon.com/primers_and_pressure.php
Re: Does using Palma brass alter chamber pressure?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ArmchairElite</div><div class="ubbcode-body">I'm glad you shared that bit about your primers getting punched through. I have been using cci br4 primers because of their cup thickness. Nice to know that my caution was warranted. Since small rifle primers are not as thick as their larger cousins I wanted to get the thickest non magnum primer available. This link has that info on primer thickness if your interested. The one they do not show is the cci #41 small rifle military primer. It is the same thickness as the br4, but a magnum and it has shorter dimensions to avoid a slam fire in autos.
http://www.jamescalhoon.com/primers_and_pressure.php </div></div>
I cant speak for 308 Palma loads but I know in my 6.5x47 I use the Wolf Smal Rifle Magnum primer. Zero change in MV or pressure. With the Wolf SRM primer the only different is cup thickness.(Thanks Jedi for teaching me this) If there is zero difference in Mag vs Non Mag I dont know why you wouldnt want to go with the thicker cup? I see the Palma as a fast car... You CAN drive it fast but dont have too, but if your slinging 30 cal 155's to 1000 yards and are using a casing that has a smaller primer and can take a resonable amount of added pressure why not?
Just my .02
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ArmchairElite</div><div class="ubbcode-body">I'm glad you shared that bit about your primers getting punched through. I have been using cci br4 primers because of their cup thickness. Nice to know that my caution was warranted. Since small rifle primers are not as thick as their larger cousins I wanted to get the thickest non magnum primer available. This link has that info on primer thickness if your interested. The one they do not show is the cci #41 small rifle military primer. It is the same thickness as the br4, but a magnum and it has shorter dimensions to avoid a slam fire in autos.
http://www.jamescalhoon.com/primers_and_pressure.php </div></div>
I cant speak for 308 Palma loads but I know in my 6.5x47 I use the Wolf Smal Rifle Magnum primer. Zero change in MV or pressure. With the Wolf SRM primer the only different is cup thickness.(Thanks Jedi for teaching me this) If there is zero difference in Mag vs Non Mag I dont know why you wouldnt want to go with the thicker cup? I see the Palma as a fast car... You CAN drive it fast but dont have too, but if your slinging 30 cal 155's to 1000 yards and are using a casing that has a smaller primer and can take a resonable amount of added pressure why not?
Just my .02
Re: Does using Palma brass alter chamber pressure?
The Theory behind using small rifle primers in 308 is that the powder burns much more consistently than a primer explodes. Since primers change in behavior so much from one to another it's best to use the smallest/least powerful one that will still do the job properly to lessen that variable. If I use a magnum I am undermining the purpose of the Palma brass by introducing a large irregular explosion. However, if I ever decide to try another primer it will be a Wolf. I hear they are very consistent, much less expensive, and have a thick cup. You may be on to something.
Here is a link showing a picture of a Wolf primer firing next to the powerful Remington 7 1/2. Scroll about 1/3 down.
http://bulletin.accurateshooter.com/category/reloading/page/10/
By the way, how do I paste in a quote from someone else in my post like you did with me? I'm very new at this.
The Theory behind using small rifle primers in 308 is that the powder burns much more consistently than a primer explodes. Since primers change in behavior so much from one to another it's best to use the smallest/least powerful one that will still do the job properly to lessen that variable. If I use a magnum I am undermining the purpose of the Palma brass by introducing a large irregular explosion. However, if I ever decide to try another primer it will be a Wolf. I hear they are very consistent, much less expensive, and have a thick cup. You may be on to something.
Here is a link showing a picture of a Wolf primer firing next to the powerful Remington 7 1/2. Scroll about 1/3 down.
http://bulletin.accurateshooter.com/category/reloading/page/10/
By the way, how do I paste in a quote from someone else in my post like you did with me? I'm very new at this.
Re: Does using Palma brass alter chamber pressure?
I have been using CCI 450 small rifle magnum in the Palma brass for about one year. I found 45 grains of varget to be most accurate load. One of the benchrest shooters in my club tested the accuracy of rounds with cci 450 against rounds with large rifle primer. Both using 45 grs. of Reloader 15. He found they were the same as far as accuracy, and this is one of those guys with the expensive front rest and a 3 oz jewell triger, bat action and all kinds of real expensive stuff.
All rounds fired were 175 SMKs.
Quite a few competative shooters in my club shoot 45 grains of either reloader 15 or varget behind a 175 SMK.
I'm the only one using Palma brass.
I shoot them in TRG-22. I have only had to neck size them after FLS when new. Bolt never hard to open or close.
I have been using CCI 450 small rifle magnum in the Palma brass for about one year. I found 45 grains of varget to be most accurate load. One of the benchrest shooters in my club tested the accuracy of rounds with cci 450 against rounds with large rifle primer. Both using 45 grs. of Reloader 15. He found they were the same as far as accuracy, and this is one of those guys with the expensive front rest and a 3 oz jewell triger, bat action and all kinds of real expensive stuff.
All rounds fired were 175 SMKs.
Quite a few competative shooters in my club shoot 45 grains of either reloader 15 or varget behind a 175 SMK.
I'm the only one using Palma brass.
I shoot them in TRG-22. I have only had to neck size them after FLS when new. Bolt never hard to open or close.
Re: Does using Palma brass alter chamber pressure?
If they are working then that's what's important. I was just under the understanding that using a magnum primer lessened the advantage of the Palma brass. If you're using a primer with a big unpredictable explosion then it's not really an advantage to use the small primer. Of course, it can't hurt that your using arguably the best rifle their is. I'm using an HS Precision Savage with a 1/10 twist so my rifle should like a little longer bullet. Makes sense that we are using basically the same load with the exception of bullet length because of our rifles different twist rates. Primer pockets don't tend to open up like regular brass so I'm really paying attention for stress signs, but nothing so far. The complaint against Palma brass was the increased chance of hang fires, but I've never had any problems at all. When these get worn out (someday) I'm going to get more of the same. I only got them because they were out of the regular Lapua brass at the time. I'm glad they were. I will be trying 208 amax next. If they are going to show stress signs those 208s should reveal them.
If they are working then that's what's important. I was just under the understanding that using a magnum primer lessened the advantage of the Palma brass. If you're using a primer with a big unpredictable explosion then it's not really an advantage to use the small primer. Of course, it can't hurt that your using arguably the best rifle their is. I'm using an HS Precision Savage with a 1/10 twist so my rifle should like a little longer bullet. Makes sense that we are using basically the same load with the exception of bullet length because of our rifles different twist rates. Primer pockets don't tend to open up like regular brass so I'm really paying attention for stress signs, but nothing so far. The complaint against Palma brass was the increased chance of hang fires, but I've never had any problems at all. When these get worn out (someday) I'm going to get more of the same. I only got them because they were out of the regular Lapua brass at the time. I'm glad they were. I will be trying 208 amax next. If they are going to show stress signs those 208s should reveal them.
Re: Does using Palma brass alter chamber pressure?
What is below is a small portion of an article by German Salazar, regarding primers.
Simply stated, the small primer in the .308 case is at the low end of acceptable ignition under ideal conditions - and conditions are often not ideal. As ambient temperature drops and especially if ignition systems are modified (uselessly, I might add) with lighter firing pins, ignition reliability declines. A system which is marginally acceptable under ideal conditions will then begin to produce hangfires and misfires. In many cases, when shooters used the Remington small primer cases as a full-length .308, this is exactly what happened. Heavier powder charges and slow-burning powders further add to the difficulty of ensuring reliable ignition. With the typical Palma load of 46 grains of Varget, a moderately slow powder, I will venture to say that many small primers will be inadequate to ensure adequate ignition under all environmental conditions.
What is below is a small portion of an article by German Salazar, regarding primers.
Simply stated, the small primer in the .308 case is at the low end of acceptable ignition under ideal conditions - and conditions are often not ideal. As ambient temperature drops and especially if ignition systems are modified (uselessly, I might add) with lighter firing pins, ignition reliability declines. A system which is marginally acceptable under ideal conditions will then begin to produce hangfires and misfires. In many cases, when shooters used the Remington small primer cases as a full-length .308, this is exactly what happened. Heavier powder charges and slow-burning powders further add to the difficulty of ensuring reliable ignition. With the typical Palma load of 46 grains of Varget, a moderately slow powder, I will venture to say that many small primers will be inadequate to ensure adequate ignition under all environmental conditions.
Re: Does using Palma brass alter chamber pressure?
Yeah, I read that and it worried me. Fortunately he is wrong. Lapua even said that shooting with faster burning powder like Varget should be fine. If I was going to use RL-17 I would consider using a magnum primer, but Varget doesn't need it. Maybe if you shoot in below freezing conditions, but I don't. The first few times I shot with them I was really waiting for something to not work right. He had me a bit worried. As long as you're using Varget or RL-15 or something like that you will never have a problem. I switched from CCI 400 to CCI BR4s because I was getting cratering and I was concerned about a primer puncture. The CCI 400s never failed to give complete ignition of the powder though. I just wanted a thicker cup.
Just out of curiosity, what kind of scope did you put on your TRG 22? My IOR just came in the mail while I was writing this.
Yeah, I read that and it worried me. Fortunately he is wrong. Lapua even said that shooting with faster burning powder like Varget should be fine. If I was going to use RL-17 I would consider using a magnum primer, but Varget doesn't need it. Maybe if you shoot in below freezing conditions, but I don't. The first few times I shot with them I was really waiting for something to not work right. He had me a bit worried. As long as you're using Varget or RL-15 or something like that you will never have a problem. I switched from CCI 400 to CCI BR4s because I was getting cratering and I was concerned about a primer puncture. The CCI 400s never failed to give complete ignition of the powder though. I just wanted a thicker cup.
Just out of curiosity, what kind of scope did you put on your TRG 22? My IOR just came in the mail while I was writing this.
Re: Does using Palma brass alter chamber pressure?
I put a Premier Heritage 5-25x56 mounted in Badger rings on it.
I put a Premier Heritage 5-25x56 mounted in Badger rings on it.
Re: Does using Palma brass alter chamber pressure?
That works! Something else I can't afford, but fitting for that rifle. I just got a fixed 16x IOR today. It's the only way I could afford that level of glass. I'm very happy with it though for $800. I like to look at the Premier, Hinsoldt, S&B, Mars etc... But I don't think I could ever afford one. But if I could, I would.
That works! Something else I can't afford, but fitting for that rifle. I just got a fixed 16x IOR today. It's the only way I could afford that level of glass. I'm very happy with it though for $800. I like to look at the Premier, Hinsoldt, S&B, Mars etc... But I don't think I could ever afford one. But if I could, I would.
Re: Does using Palma brass alter chamber pressure?
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Yeah, I read that and it worried me. Fortunately he is wrong. Lapua even said that shooting with faster burning powder like Varget should be fine.</div></div>
Where did Lapua say that. I'd like to read the article or whatever it was.
Was Lapua's opinion based on the absence of knowedge, i.e., they never tested Palma brass with magnum primer? In other words did they say magnum primer is not needed, dangerous or whatever.
Or did they conduct testing with regular sr primer and sr magnum primer and have based opinion that magnum primer is not needed on real empirical data.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Yeah, I read that and it worried me. Fortunately he is wrong. Lapua even said that shooting with faster burning powder like Varget should be fine.</div></div>
Where did Lapua say that. I'd like to read the article or whatever it was.
Was Lapua's opinion based on the absence of knowedge, i.e., they never tested Palma brass with magnum primer? In other words did they say magnum primer is not needed, dangerous or whatever.
Or did they conduct testing with regular sr primer and sr magnum primer and have based opinion that magnum primer is not needed on real empirical data.
Re: Does using Palma brass alter chamber pressure?
The link is dead now. Fortunately I found the quote.
...you're perfectly correct that this is pretty much the outer limit of what a small primer can reliably ignite. To that end, we're marketing this as a competitive case, and not recommending it fro many hunting applications. Extreme cold temps or harder to ignite charges of slow burning powders could be a problem here with hangfires or that sort of thing. However, with the normal powders used for competition (such as Varget) and the conditions competitions are normally held under, this is not a problem. Give them a try, and see if they don't help reduce the variables I've discussed here.
Thanks,
Kevin Thomas
Lapua USA
Nobody ever said they were dangerous. If anything, using CCI 450 is safer than using CCI 400 because they have thicker cups like CCI BR4. I'm just saying that the point of using small primers is that they give a more predictable explosion than large primers. Powder burns much more predictably than primers explode. So the smaller the primer explosion the more predictable and repeatable the speed. I'm getting an ES of 7fps so I know it works. If you are using a more powerful primer you negate some of this respectability because it's going to explode a little different each time and lite the powder a little differently each time. It's easier to predict a firecracker than it is to predict TNT. If you lite the powder in a small spot the very predictable burn rate of the powder will give you very repeatable results.
Like everything their is a downside. Since using small primers puts you closer to the minimum requirements for ignition you my have a problem in extreme cold or when using slow burning powder that is harder to lite. My grampa lives in Idaho and I know it gets very cold. You may need to use a magnum primer in that kind of weather. I don't really know. You would have to try it to find out.
Here are some pictures of primer explosions(1/2 way down). The Remington 7 1/2 is the Remington magnum. It is somewhat more powerful than the CCI 450 but you will get the idea.
http://riflemansjournal.blogspot.com/2009/06/primers-small-rifle-primer-study.html
The link is dead now. Fortunately I found the quote.
...you're perfectly correct that this is pretty much the outer limit of what a small primer can reliably ignite. To that end, we're marketing this as a competitive case, and not recommending it fro many hunting applications. Extreme cold temps or harder to ignite charges of slow burning powders could be a problem here with hangfires or that sort of thing. However, with the normal powders used for competition (such as Varget) and the conditions competitions are normally held under, this is not a problem. Give them a try, and see if they don't help reduce the variables I've discussed here.
Thanks,
Kevin Thomas
Lapua USA
Nobody ever said they were dangerous. If anything, using CCI 450 is safer than using CCI 400 because they have thicker cups like CCI BR4. I'm just saying that the point of using small primers is that they give a more predictable explosion than large primers. Powder burns much more predictably than primers explode. So the smaller the primer explosion the more predictable and repeatable the speed. I'm getting an ES of 7fps so I know it works. If you are using a more powerful primer you negate some of this respectability because it's going to explode a little different each time and lite the powder a little differently each time. It's easier to predict a firecracker than it is to predict TNT. If you lite the powder in a small spot the very predictable burn rate of the powder will give you very repeatable results.
Like everything their is a downside. Since using small primers puts you closer to the minimum requirements for ignition you my have a problem in extreme cold or when using slow burning powder that is harder to lite. My grampa lives in Idaho and I know it gets very cold. You may need to use a magnum primer in that kind of weather. I don't really know. You would have to try it to find out.
Here are some pictures of primer explosions(1/2 way down). The Remington 7 1/2 is the Remington magnum. It is somewhat more powerful than the CCI 450 but you will get the idea.
http://riflemansjournal.blogspot.com/2009/06/primers-small-rifle-primer-study.html
Re: Does using Palma brass alter chamber pressure?
I just spoke with Kevin Thomas of Lapua on the phone. He stated that they have not tested the CCI 450 primer specifically in the Palma brass and that there is no standard by which primer ignition is judged. I believe I stated that correctly.
He did recommend sr primers and based on our converstation I'm going to try some Wolf sr primers and compare them against the 450's I'm using.
One another note we disscussed a hangfire, probably millisecond
that I was having when I was using blc2 and cci450 magnum primer. I only relized the hangfire by the difference in ignition (you know pulling trigger to gun going bang) when I tried the varget. Kevin said with the blc2 being a ball powder it was baseline harder to ignite. Well I can say the 450 magnum was not up to that task.
I just spoke with Kevin Thomas of Lapua on the phone. He stated that they have not tested the CCI 450 primer specifically in the Palma brass and that there is no standard by which primer ignition is judged. I believe I stated that correctly.
He did recommend sr primers and based on our converstation I'm going to try some Wolf sr primers and compare them against the 450's I'm using.
One another note we disscussed a hangfire, probably millisecond
that I was having when I was using blc2 and cci450 magnum primer. I only relized the hangfire by the difference in ignition (you know pulling trigger to gun going bang) when I tried the varget. Kevin said with the blc2 being a ball powder it was baseline harder to ignite. Well I can say the 450 magnum was not up to that task.
Re: Does using Palma brass alter chamber pressure?
Interesting. I knew that I would be safe using Varget since he said that powder would be fine specifically. I have considered the wolf primers because they are a very small consistent ignition source. I just didn't want to press my luck. I will try them after I use up some of my BR4s(just bought a 1,000) if they work well for you. Update the thread after you try them out.
I put my IOR on yesterday. Same 16x as my PST, but much better detail. So much clarity downrange.
Interesting. I knew that I would be safe using Varget since he said that powder would be fine specifically. I have considered the wolf primers because they are a very small consistent ignition source. I just didn't want to press my luck. I will try them after I use up some of my BR4s(just bought a 1,000) if they work well for you. Update the thread after you try them out.
I put my IOR on yesterday. Same 16x as my PST, but much better detail. So much clarity downrange.
