Switching from CCI Match to Magmun Primers - Pressure Change Question

358Scout

358Scout

Regular
Rating - 100%
72   0   0
Location
Saskatoon
I have a 45-90 Shiloh Sharps and am using assorted smokeless powders. For the last while I've been casting 480gr but having unusual problems.
My powder is'nt all burning. Its changed from the traditional grey/ black to a sand color. I assumed it was maybe as a result of the online bullet lube recipes.
I last used SPG and found its doing the same. Someone yesterday said I should switch to magnum primers that because of the case size the CCI may not be enough to
ignite all powder. Picked up some Federal 215 LMRP. Cant seem to find information on powder reduction if switching to these or what type of pressures these will result in.

Any links or advise greatly appreciated.
 
Unless your over max levels it won't have an effect. If your super paranoid use 1gr less of powder and work up.
 
The load I'm trying uses a Hornady 325 GR FTX with 54 grains IMR 3031
The load I pulled off the net which seems to be from a book or magazine used Hornady 300 JHP, same powder charge @ 1740 - 1752 fps.
They used a WLR primer and CCC case. The only other notes are Case Expansion: Near Max
 
Spawn-Inc said:
Unless your over max levels it won't have an effect. If your super paranoid use 1gr less of powder and work up.
Click to expand...

i disagree...

switching from regular to magnum primers will cause 1 or 2 things to happen -

1) you get more consistent ignition in a wider range of temp, good thing..

and possibly a bad thing

2) is dependent on your rifle. that bigger and hotter ignition causes more powder to ignite simultaneously , this in turn will cause a steeper pressure spike. which could cause you to have to reduce your load resulting in a lower velocity. if you switch from a standard to magnum primer, i highly suggest that you load up a few rounds and find out where the pressure signs start
 
ultimate_monkey said:
i disagree...

switching from regular to magnum primers will cause 1 or 2 things to happen -

1) you get more consistent ignition in a wider range of temp, good thing..

and possibly a bad thing

2) is dependent on your rifle. that bigger and hotter ignition causes more powder to ignite simultaneously , this in turn will cause a steeper pressure spike. which could cause you to have to reduce your load resulting in a lower velocity. if you switch from a standard to magnum primer, i highly suggest that you load up a few rounds and find out where the pressure signs start
Click to expand...

i meant nothing bad will happen, common sense dictates that when you change something in your load you should work up to it again.
 
I don't have a 45-90 but in my 45-70 I find some powders wont fully burn no matter what primer I use. The peak pressure just isn't high enough to burn all the powder.
Are you using faster powders or medium burn rate powders? I find I have to use pretty fast powders to get it all to burn.
Favourite for full house 45-70 is H4198 though I did just get a jar of IMR3031 to try out.
H4895 and IMR4895 both work but always leave unburnt powder.
SR-4759 (discontinued sometime this year) is great for medium power loads and always burns completely.
I use an assortment of shotgun powders for plinking loads (Bluedot and Unique mostly). They're dirty but never leave unburnt flakes.

I recently started switching to magnum primers and am working up loads from start again to find the accuracy sweet spot in all my scoped rifles. I really don't care about getting an extra few fps if it sacrifices any accuracy.
For reduced/plinking loads (mostly with cast bullets) I switch between regular and magnum primers all the time and don't worry about it. When I am barely producing enough pressure to obturate the case (~15k psi?), an extra 3-5% pressure wont do anything in a gun designed to handle 50k+ psi (that's my rifles, I don't know what a 45-90 Shiloh is proofed at).
 
Those powders are both fairly fast so should burn fully with enough pressure. What sort of pressure range are you loading them to? I load H4198 down to ~20k psi (based on load data so we're talking really rough numbers) and get a good burn. Re7 is actually a little faster.
 
No idea what the pressure ranges are. As I noted above thats all the info that was originally printed from what people say came from an old IMR manual.
The load listed above were noted to give excellent accuracy out of a Shiloh Sharps 28 and 34" barrel with Hornady 300gr JHP. Since Cabelas doesnt carry these bullets
and Wholesale Sports is out I'm going to the closest - the 325gr FTX.
 
Where are you getting your data? Don't sse .45-90 on Hodgdon's site. Just curious.
Anyway, if you're getting unburned powders a magnum primer won't necssarily fix it.
 
You must log in or register to reply here.
Back
Top Bottom