Primer question loading for .220 Swift

[Swift]

Hi guys! New to the forum here. Have been reading for a couple of weeks and decided to jump on board with some questions. I load primarily for rifles at the moment. .220 Swift, .243 Winchester and 22-250. I don't shoot as much as I would like, but am trying to find more time to do it. I've been invited on a prairrie dog hunt in a couple of weeks so I'm trying to load up enough ammo for the Swift as I'm pretty sure I won't be able to find any factory ammo if I run short. I've had my pet load using CCI 200 primers, 42.5 grains of H380, and 50 grain Hornady V-Max bullets. I let my primer supply get low and bought some CCI Br 2 primers thinking that would be as close as I could get for a while. I loaded a few rounds up with the Br 2 primers backing off the H380 to 39 grains and figured I'd work up from there. The cases are new Winchesters, the same as I've been shooting. I full length resized the new brass to start with. I typically neck size only and after a few loadings I have to full length size as they get too hard to eject. The 39 grain loads ejected quite easily but the primers are pretty obviously flattened. There are no extracter marks and the brass looks perfect. My groups aren't near as good as the full loads with the 200 primers. I know I'm pushing pretty hard at 42.5 grains as I believe the chrony was at 4100fps when I first developed the load. I tried three different bullets, three different powders, and worked the loads up to max in four steps. It just so happens that the most accurate load was also the fastest. I was hoping to slow it down a little and take it a little easier on the barrel, but with consistent 1/2" groups, I'll take my chances with the barrel. I haven't got the chrony out to know how hard I'm pushing things yet, but is it possible that benchrest primers are that much softer or are they building more pressure than the 200's? Do primers make that much difference in accuracy? Are flattened primers a sure sign of high pressure even when the cases extract easily? I want to be safe but I've never seen these signs before so I'm not sure how to interperet them. Thanks.

Greg

 

[mregunz]

Wow guy,I looked in my Hodgdon,manual and that's only a grn.below minumum,My book is a old one but still work's,Could be low pressure,in my understanding from 2 different gunsmith's I've been told low pressure can react just like hi-pressure.You might try going up a grn.and see what happen's if it get's worse I'd not go anymoreAnd I'd find some diff. primer's at that point.I have a .220 fast(swift).And I shoot 42.0 grn's of H414 behind a 50 grn.v-max.And I use Winchester Large rifle primer's and it shoot's Like a house -ah-fire.I have Pac-nor brl.and a bed'd action. And it consistantly shoot's 1/4" group's at a 100yd's.But I bet with that ld a you'll at least duplicate ur 1/2' ld's.Maybe it'll even tight'n up the thing is at the price of powder a person hates to buy a lb. and then not have it work maybe a buddy has some H414 you can borrow and pickup a 100win.lg.rifle pri.'s.Boy those 50-v-max are death on P.dog's ain't they I love my 50 grn's misslesWith my 28" brl that' ld is running 3850-3900 vel. chrono'd,not gussing.Hope thing's work out for you and good shooting and huntin.....

 

[ArchAngelCD]

Welcome to the forum "Swift".

From everything I've read and seen from using BR primers they are the same exact primers as standard CCI primer. The only difference is the workers they use to assemble the BR primers are their best workers. If you were asking about #34 NATO primers they would be more in line with Magnum primers but the BR primers are not.

Are you using a new lot of powder??

 

[243winxb]

Are flattened primers a sure sign of high pressure

No, flat is ok. When primers look like this, its NOT Ok

 

[Swift]

Thanks for the replies! I don't have time to post pictures, I will try tonight. My primers are flat, but don't have the protruding ring around the firing pin indentation. As I said the cases extracted very easily so I don't think I'm dangerously over pressure. When I bought the benchrest primers I thought I'd read somewhere that they were the same as 200's, just asssembled with tighter tolerances. Maybe I'll try to work the load up a bit this weekend and try to get the chrony out. I shot a three shot group last night with the 200 primers and two were touching and the third was less than a half inch out. That's pretty normal for that load when the wind is right and I do my part. The other loads are barely breaking an inch. Maybe I should be happy with that, but I'm used to the smaller groups and would like to keep them (or shrink them). Thanks.

Greg

 

[mregunz]

A flat primer is the first sign of hi pressure.Next half a grain of powder is dish with along with flat.Dish is like what's in the picture of the 223 brass.Have a good one swift....jerry

 

[R.Clem]

Primers make a large difference. In a 7mm STW I used to own, changing the primer only, would cause a velocity loss of up to 400 FPS and accuracy would go out to 2+ inches. With the load the rifle liked, 1/4 to 1/2 MOA was the norm. I have also seen this in other rifles over the years.
Changing one component will change everything, it then becomes time to start over and pray you can find something that is as good as what you had. In the above mentioned STW, I had over 200 different loads, only 4 of which would shoot under 1 inch at 100 yds. consistently. All of these loads worked best with one single brand of primer, no matter what the other components were.
I spent nearly 2 years shooting the STW working up loads, the first accurate load happened at load #63 the next at load #188, followed by #196 and #204.
The later 2 were changes in bullets only.
For those interested, 4055 rounds, 12 different powders, 10 different primers, 21 different bullets and 2 different cases.
The STW now belongs to my son, it will still shoots 1/4 MOA and has over 4500 rounds down the barrel. I expect it will need a new barrel before it reaches 6000 rounds, but who knows.

Ray

 

[ArchAngelCD]

When I bought the benchrest primers I thought I'd read somewhere that they were the same as 200's, just assembled with tighter tolerances.

You are correct. That's what I was trying to tell you in my first post. Of course when you change components it's always good to drop back and work up your load again but in this case both primers are CCI so it's not as critical IMO. You should get the same or better results with the BR primers as you get with the CCI200 primers...

 

[Swift]

Hi I'm back to try to post pictures. I've got four sets of three to look at. From left to right is 39 grains, 40 grains, and 41 grains of H380 with Br primers. The far right set is 42.5 grains of H380 with CCI 200 primers that I've been shooting for four or five years. They look to be a bit dished under a bright light and with a camera flash, but they don't look that bad to the naked eye. I always figured that the primers would flatten to indicate excessive pressure. The heavy (accurate) loads don't show any signs of flattening but the lighter loads primers are flattened. Now I'm getting confused. What do you guys think? Thanks.

Greg

 

[ArchAngelCD]

All but the heaviest charge look fine to me. I would worry a bit about the ones on the far right though...

 

[243winxb]

The 3 primers on the right are showing your at or near maximum. But i would want to have other high pressure signs to go with the primer before i would reduce the load. If the primer is your only indication of high pressure, i would not worry about it. Besides, you have used the load for "four or five years". When any component is changed, a different lot number, it would be best to reduce you load and work up again. When i run at maximum,i weigh each powder charge.