Sanity Check on 220 Swift AI fireforming

[Raider1v1]

My many hunting partners and I shot 760 in S. Dakota for many years on dog hunts.

Normal vs Winchester is like comparing apples and oranges, norma is thicker and may give you more grip on your bullet....

Just be careful with varget, pressure spikes abound and I am talking about going from a little flat edge to a blow primer.

You should not be scared of 760 unless you leave your ammo out in the sun, in addition to running a red hot load to begin with.

Good luck

Gotcha. I did know that norma was thicker and id probably have to compare data and work up to other published loads like normal.

Ill report back after i get some varget loads fired.

 

[Dusty Stevens]

My many hunting partners and I shot 760 in S. Dakota for many years on dog hunts.

Normal vs Winchester is like comparing apples and oranges, norma is thicker and may give you more grip on your bullet....

Just be careful with varget, pressure spikes abound and I am talking about going from a little flat edge to a blow primer.

You should not be scared of 760 unless you leave your ammo out in the sun, in addition to running a red hot load to begin with.

Good luck

Keep them long range bullets on the dash in the sun.

 

[ranger3]

I have used H380 and IMR 4064 in my 220 swift for years. gave good results and no pressure. you are jammed a long ways and I would be concerned using Benchmark in a Swift. Way too fast and creating pressure.

 

[CT10ring]

I have 2 220 Swifts. Varget at 38.0 RL-15 38.0 about max for my comfort. 52-55g bullets. althou the point of an AI is more powder...
Make it more of a slower powder. Not an expert as guys posting prior. I's say no reason to have bolt bushed per se, but your primers will look
nicer . Greg Tannel fast turnaround at this. One of his specialities, sure many other smiths can bush bolt & pin. I shoot my 220 SW in PD
towns, me- always have 1-2 other rifles nearby to use while it cools...and I shoot it sparingly. good info for all from your post-

 

[CT10ring]

Raider1, my sanity check on new loads, fwiw.

 

[Raider1v1]

I have 2 220 Swifts. Varget at 38.0 RL-15 38.0 about max for my comfort. 52-55g bullets. althou the point of an AI is more powder...
Make it more of a slower powder. Not an expert as guys posting prior. I's say no reason to have bolt bushed per se, but your primers will look
nicer . Greg Tannel fast turnaround at this. One of his specialities, sure many other smiths can bush bolt & pin. I shoot my 220 SW in PD
towns, me- always have 1-2 other rifles nearby to use while it cools...and I shoot it sparingly. good info for all from your post-

ill report back when i do the loads w/ varget. i think the primers were flowing/cratering due to the extra overpressure of my terribly over max loads. based on you stopping at 38gr, and hornady saying max is 37.0; i think ill start at 36 and go to 38 to see what i get and what fps I am seeing.

what length do you have your swifts at? the 2.680 COAL or do you have them .20 or so from the lands?

i am planning on having mine touch the lands a bit to keep the case against the boltface.

 

[CT10ring]

My 220 swift loads are at 2.800", lands are at 2.820" for a 52g Berger. I'm not sure my info is strictly applicable for an improved case.
My Sierra guide for 220 Swift shows max of 38.0g RL-15 w a 52g bullet. Do you know the distance to lands?

I'd guess RL-15, Varget or H4350 would all be good powders to start with. I'd load down 10% to start. 38.0g x -10% approx. 35.0g.

From your pictures, I'd say your primers are seriously flattened, a def sign of over pressure.
Also seems that the firing pin hole in bolt is larger than it should be, causing primer flow, regardless of your loads.

The brass was hard to get out of your chamber because the pressure was so high they were sticking to your chamber.
Sticky cases on bolt opening are a sign of overpressure. And when you are shooting in summer temps, it will be more prevalent.

Of course, you must take responsibility for your loads for your specific components. check how much faster
Benchmark is vs. RL-15, Varget & H4350 in this chart. Made for less powder in a smaller case.

post your results & good shooting!