Im using .335 which is what redding said to use I couldn't get my hands on a micrometer at the time and now I'm wanting to play with neck tension and seating depth.So like the title says what redding bushing are you using with FC brass and 175 smk
What redding bushing is everyone using for FC brass and 175smk
- Thread starter qkieler
- Start date
Lapua Brass & FC Brass - .308WIN / 175SMK, 168SMK & 155 Scenar - .335 bushing = .002 neck tension
Privi Brass & Win Brass - .308WIN / 175SMK, 168SMK & 155 Scenar - .332 bushing = .002 neck tension
Privi Brass & Win Brass - .308WIN / 175SMK, 168SMK & 155 Scenar - .332 bushing = .002 neck tension
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Federal 'can' have some thinner necks, so I believe I use a .334" for a couple of thousandths of neck constriction. You always want a few different sizes to accomodate various brands of brass anyhow and to have a larger .249"-.250" step-down bushing, if you're shooting factory barrels which blow out the necks.
Chris
Chris
I use .334" as well. Federal Brass is thicker than Winchester Brass (which I use .332") but it is not as thick as RWS.
Nowadays I prefer the Lee Collet Neck Sizing Die. The thing about the necks of brass is they get thinner over time as they get fired and trimmed. Thus I found that the original .334" bushings no longer work for the same piece of brass after several firings and trimmings. I don't need to worry about proper bushing size with the Lee Collet Neck Sizer.
Nowadays I prefer the Lee Collet Neck Sizing Die. The thing about the necks of brass is they get thinner over time as they get fired and trimmed. Thus I found that the original .334" bushings no longer work for the same piece of brass after several firings and trimmings. I don't need to worry about proper bushing size with the Lee Collet Neck Sizer.
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My necks are at .342 after firing redding said that anything over .010 I would need a step down bushing but I've also read that anything over.005 can give you runout problems I was thinking of getting a .337 or .338 for when my brass gets a little older. Has anyone ever played with a thousandths different bushing and gotten any noticeable gains in accuracy?
I've been using a .337" for Federal brass that's been MFG. within the past 6-7 years. Some 25+ Y/O brass had thinner necks, but all of the new stuff is thick. For my gas gun, I use a .335" for .003" neck tension.
I always thought Redding stated .008", or less, for preserving springback, so that's why we use a step-down bushing. Many here like that .005" number, but I don't think that there are any hard studies on the matter.
If you're blowing your necks out to .342" (and my Savage goes to .344ish) then a .338" bushing might be appropriate, especially if you have some thin walled Winchester brass. Not all Winnies are thin and they deviate a bit, some being thinner and some closer to Federal and RP in thickness.
Still, this is why I run tandem Redding bushing neck sizer dies in a separate toolhead for my Dillon 550b. I have my body die and both neck bushing dies on one toolhead, with the step-down bushing in the #4 station and no decapping rod, the body die in the #3station and finally the second bushing neck sizing die, with decapping rod and the final sizing bushing, in station 1.
If you're using a SS press, you'll have to do two, or three, passes to achieve the same result.
I'm getting a bit anal, but that's how I do it for .308 Win and .223 Rem.
Chris
I'm confused I guess.. why don't you measure your case neck thickness and then decide what tension you want, after that decision is made buy the appropriate bushing?
My LC (turned to .015) = .015 x 2 = .030 + .308 = .338 - .004 tension = .334 bushing
My LC (turned to .015) = .015 x 2 = .030 + .308 = .338 - .004 tension = .334 bushing
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I use my 334 bushing for Rem, Lapua & Fed 308 cases, 331 for Win, you cant argue with the results Im getting, 1/2min or less out to 300yds.
I had hornady brass measure .0125 another lot at .0145
Similar results with Remington and winchester brass. Measure it and pick the right bushing.
Similar results with Remington and winchester brass. Measure it and pick the right bushing.
thanks guys the 1x fired brass i have was shot from a gun with a tighter chamber so im right at the .005 mark with the.335 bushing i will just have to order a stepdown bushing when all of that brass is shot from my gun i havent measured the thickness of my brass and done the math because i was told calipers wouldnt be accurate enough for that and i couldnt get a micrometer at the time so i just measured OD of the neck and called redding. Im running a single stage press so the stepdown will suck when it comes to that but o well
Turning your necks will help remove some of the variable and guesswork involved.
I tried neck sizing in one step, and two steps. For me, and for whatever reason, I was getting less runout on the average sizing down in one step. If your neck walls are consistent in material characteristics and thickness, then springback should also be consistent. What counts is what shows up on paper downrange. Find the bushing that sizes and gives the final neck tension that your rifle/ammo combo likes, and go with that. If you find you get less runout and better accuracy by stepping down, then go with that too. There is no one answer. But IMO, if you don't turn necks, you are going to have inconsistent neck tensions and bullet runout regardless.
I tried neck sizing in one step, and two steps. For me, and for whatever reason, I was getting less runout on the average sizing down in one step. If your neck walls are consistent in material characteristics and thickness, then springback should also be consistent. What counts is what shows up on paper downrange. Find the bushing that sizes and gives the final neck tension that your rifle/ammo combo likes, and go with that. If you find you get less runout and better accuracy by stepping down, then go with that too. There is no one answer. But IMO, if you don't turn necks, you are going to have inconsistent neck tensions and bullet runout regardless.
