IMR 4007ssc in 220 swift

Originally Posted By: CatShooter Keep in mind that my .220 Swift is a Remington 40-XB/SS with a 28" tube and a long throat. Loaded COL is 2.950".
If you try to get 4,100 fps with a 24" barrel and a COL of 2.80", you are going to have to pull the trigger a damm lot harder than I do.
Interested to see what your brass oal is, and just how compressed your load is if at all. I have a 26" barrel, but I'll take what it will give, just hoping I can do better than what I'm at with IMR 4064.
 
Originally Posted By: travjcOriginally Posted By: CatShooter Keep in mind that my .220 Swift is a Remington 40-XB/SS with a 28" tube and a long throat. Loaded COL is 2.950".
If you try to get 4,100 fps with a 24" barrel and a COL of 2.80", you are going to have to pull the trigger a damm lot harder than I do.
Interested to see what your brass oal is, and just how compressed your load is if at all. I have a 26" barrel, but I'll take what it will give, just hoping I can do better than what I'm at with IMR 4064.

My load is not compressed.

In fact there is more room, and I have loaded another bunch of test loads to find the pressure/velocity limits - in the end, I will use the most accurate "reasonable" load, but I am curious.
 
Well, 32 rounds down the tube this eve, and Iv'e nearly matched my existing IMR 4064 load velocity. I'm beginning to see a small amount of primer flattening with WLR primers, much less than I'm getting with 4064 at the same velocity. To say the least I'm well over published max load for IMR 4007SSC and seeing plenty of room for improvement. Not real impressed with my standard deviation numbers compared to those of my 4064 loads, but I'm going to set that aside for now. Also finding as the loads increase the SD numbers are getting better an so are the groups, go figure! I have had several promising groups (when I was focused well) which are better than those with 4064. All in all, I'm beginning to see promise in IMR 4007SSC as "THE" 220 Swift powder for me.
 
Also, as Smokeless stated, 39gr of IMR4007SSC is a good starting point. I have stepped up .5gr increments from 39.5gr to 42gr finding increased velocity increase in the last 2 steps. At 41.5gr, began to see some change in primer face, with little change in the next .5gr. I am going to back off .5gr and switch to a magnum primer and proceed from there. Also note, 42gr of IMR4007SSC is listed as Hodgdon website's max load for 55gr sp. Proceeding beyond this point is taken at one's own risk. Know the pressure signs and be looking for them near top loads.
 
Last edited:
After this last set of loads with magnum (WLRM) primers, I have found the area that I'm going to play with. My most accurate load was with 40gr and standard primer, with groups staying about the same untill 43gr with magnum primer. Beyond that I began seeing very high pressure signs, and did not proceed. I am going to use a 42.5gr load with standard primers as I feel this is my best compromise between velocity and accuracy, it puts me at a 3 shot average of 3921fps, while maintaining well below 1/2 moa. Thanks for tuning in, any questions feel free to ask.
 
Last edited:
3900+ with 55gr'rs is Smoke'n!

Nicely done. You watched your signs of pressure, stopped when you should have, and possibly found a new powder, and a new dimension to your Swift.
 
The gain over my loads with 4064 were decent, but the major improvement was in group size, with the added bonus of more speed. The nice thing about this powder was that pressure signs came on incrementally, not suddenly like some powders. I would definately suggest anyone in this class of case to give IMR 4007SSC a try. You just might like it!
 
Originally Posted By: travjcThe gain over my loads with 4064 were decent, but the major improvement was in group size, with the added bonus of more speed. The nice thing about this powder was that pressure signs came on incrementally, not suddenly like some powders. I would definately suggest anyone in this class of case to give IMR 4007SSC a try. You just might like it!

I tooold you that you'd like it
wink.gif


God invented IMR 4007 SSC for the .220 Swift (and the 22-250 too
wink.gif
)
 
Oh I definately like the powder, my only complaint is that my Chargemaster has a [beeep] of a time not over-throwing loads with it. I need to do the McD's straw mod to it to slow the trickle speed down.
 
I had purchased a bottle of 4007SSC to load in my swifts, but had not tried it until I saw this thread. I have a M700 VS SF that's been bedded, trigger taken down to 20 oz., etc. that I've been having trouble getting consistent groups(five shot) under 5/8- 3/4" with 55 SBK'S or 55 NBT'S with 4064 or H380.
So I decided to try some 50 grain SBK's and 4007. The first three shots at 100yds. out of a clean, cold barrel looked like this:
pigdamage036.jpg

After that I just sighted it in and the groups were similar! Then I went out and killed eleven groundhogs!
My chronograph was doing some funny stuff as the first three shots registered just a little over 3800 for 42.5 grains, but then the second group 15 minutes later jumped up to 3980's! My 204 did the same thing, starting out a little over 3500, then jumping up over 3750, where it should be! 4007 and H 4895 should not be that temperature sensitive!
I think my Pact MK 4 has a ghost in it!
F1
 
Last edited:
Back
Top