Davy Posted July 17, 2011 Report Share Posted July 17, 2011 Any chance of a picture? My initial view is you will need to fire form these first to get the best results however my experience is such that the difference between as built and fire formed rounds including wildcats is not huge and accuracy is pretty close regardless most of the time. Link to comment Share on other sites More sharing options...
furrybean Posted July 17, 2011 Author Report Share Posted July 17, 2011 Ill try and get a picture but itll be hard to show up on a cam. I think theyre pretty close clearance so thats why they just kiss the neck when the bolt closes. Link to comment Share on other sites More sharing options...
kent Posted July 17, 2011 Report Share Posted July 17, 2011 yet another quick question. Ive made some rounds up and they chamber fine. When I examine the round there is a small patch where the neck touches the chamber. Will this really make a difference to normal hunting accuracy or do I need to buy a neck turning tool When you size the OD brass must go someplace it does not simply disapear. Neck turning works on the OD, turn it if you like but its no good if the extra brass is on the ID. I am not sure putting a neck mandrel in will always put the extra brass on the OD to be turned as the brass will spring some. The only way to sort this is to check the neck thickness of each case after neck sizing and see whats happening. It might work or it might not, normal proceedure with the calibre as explained previously is size down, check neck wall thickness and ream the ID if required as a one off thing with any thick ones. Please don't guess if you have thick necks or not, they could be ok just sized down but you will never know unless you check. Has nobody got the equipment to measure this in your shop at work? Link to comment Share on other sites More sharing options...
furrybean Posted July 18, 2011 Author Report Share Posted July 18, 2011 it must be the only thing they dont have and cant find one to order. How are you getting on with those 58gr? Have you tried them yet? Link to comment Share on other sites More sharing options...
kent Posted July 18, 2011 Report Share Posted July 18, 2011 it must be the only thing they dont have and cant find one to order. How are you getting on with those 58gr? Have you tried them yet? The 55's? just messing with some pre-lim to loading tonight, Grass can actually Hide my dog presently and you have seen the size of him! so no shooting till its cut unfortunatly Link to comment Share on other sites More sharing options...
furrybean Posted July 19, 2011 Author Report Share Posted July 19, 2011 Its a bit rought but Ive made this. Its tapped so I can use the Lee pilots and Ill drill it out and use a grub screw to add a dti to check neck thickness. Hopefully itll work Link to comment Share on other sites More sharing options...
kent Posted July 19, 2011 Report Share Posted July 19, 2011 How will it do that? am i missing something here? The DTI will not measure the thickness only the runout of the thickness, if you revolve it with the DTI reading any run out. You need a case / neck wall thickness micrometer to measure the actual thickening surely, you could try the sharp end of some veriners though they are in my experiance poor for calibration and presision Link to comment Share on other sites More sharing options...
furrybean Posted July 19, 2011 Author Report Share Posted July 19, 2011 I'm hoping as there is some play on the pilot, if I zero the dti onto the pilot it'll give me the thickness and turn it to see if it changes Link to comment Share on other sites More sharing options...
Davy Posted July 19, 2011 Report Share Posted July 19, 2011 I'm hoping as there is some play on the pilot, if I zero the dti onto the pilot it'll give me the thickness and turn it to see if it changes That is exactly how the SinInt version works, the shaft pilots through the primer flash hole and the measuring area of the diameter is just under the neck size so you get very little run out or error. Shout if you need a picture of one in use. Link to comment Share on other sites More sharing options...
furrybean Posted July 19, 2011 Author Report Share Posted July 19, 2011 So I've used a mandrel that's included in the nk sizer so the excess should be external. Is that right? I'm hoping I'll confirm I won't need to splash out on a neck turner after all this. Lol Link to comment Share on other sites More sharing options...
furrybean Posted July 19, 2011 Author Report Share Posted July 19, 2011 Double post Link to comment Share on other sites More sharing options...
kent Posted July 20, 2011 Report Share Posted July 20, 2011 I'm hoping as there is some play on the pilot, if I zero the dti onto the pilot it'll give me the thickness and turn it to see if it changes I am loosing the plot with this, the tollerences will conspire against you i feel. Your not working with a tight cut chamber here on a custom barrel. Turning the neck is a total waste of time if your dial set up works any thickness that shows uneven will e in the inside as you have necked down not necked up. Are you thinking the expander ball will pop it to the OD after sizing? personally i doubt it as the bress springs. Generally if i am looking for the very best cases (which i wouldn't in a hunting rifle) i should remove the expander ball completely from the process as it has a detrimental effect on concentricity and use a staight neck expander mandrel as a separate operation Link to comment Share on other sites More sharing options...
furrybean Posted July 21, 2011 Author Report Share Posted July 21, 2011 The little jig works really well and Im getting .0155-.016 thickness so thick but pretty even. Link to comment Share on other sites More sharing options...
furrybean Posted July 30, 2011 Author Report Share Posted July 30, 2011 Fire formed the brass this afternoon. There was a heat haze so struggled but got consistent 22mm groups which to start with Im happy with given the conditions but ideally I want them a little tighter ultimately. The velocities were high though for the charge, about 50fps over what the Vhit manual says. Could that be a temperature issue or too much neck thickness? Link to comment Share on other sites More sharing options...
Davy Posted July 30, 2011 Report Share Posted July 30, 2011 Could be down to temperature. Did the ammunition chamber OK, were the bullets tight to seat when you were building them and did you see any sign if over pressure? What is the neck diameter of loaded brass? Link to comment Share on other sites More sharing options...
furrybean Posted July 30, 2011 Author Report Share Posted July 30, 2011 Ammo chambered fine. Not tight to seat, or not noticably. Got o/p signs on one load so had to stop a grain off max. .315 loaded so at max SAMMI spec Link to comment Share on other sites More sharing options...
Davy Posted July 30, 2011 Report Share Posted July 30, 2011 What were the over pressure signs? There are so many things that could bump pressure up, did you get a chance to chrono the load? According to the internet .315 is fine however I should have a chamber drawing for 7mm08, I will dig it out. Link to comment Share on other sites More sharing options...
furrybean Posted July 30, 2011 Author Report Share Posted July 30, 2011 Tight bolt lift and a runny primer. Link to comment Share on other sites More sharing options...
furrybean Posted July 30, 2011 Author Report Share Posted July 30, 2011 And it was 75fps over the given max velocity with a grain to go! Link to comment Share on other sites More sharing options...
Davy Posted July 30, 2011 Report Share Posted July 30, 2011 Drop it back half a grain and see how it goes with the fire formed brass. Link to comment Share on other sites More sharing options...
furrybean Posted July 30, 2011 Author Report Share Posted July 30, 2011 Cheers for helping me out with this. The load is okay so I can fireform while I shoot it and play with seating depth. Once all the brass is fireformed I guess I'll have to redevelop a load?! Link to comment Share on other sites More sharing options...
Davy Posted July 30, 2011 Report Share Posted July 30, 2011 Cheers for helping me out with this. The load is okay so I can fireform while I shoot it and play with seating depth. Once all the brass is fireformed I guess I'll have to redevelop a load?! I do not see a huge difference between unformed and fire formed brass accuracy wise with our rifles. Case capacity may change very slightly when it is fired. Link to comment Share on other sites More sharing options...
kent Posted July 31, 2011 Report Share Posted July 31, 2011 What are you actually trying to achieve? 22mm is very average for the gun with the load details i supplied. That said groups of this size will drop any Red you care to point it at if you do your bit. I am sorry it was chucking it down and windy when you came over. Just send us postage and i will send you some new relcom 7-08 use the two loads i gave you details on and compare Link to comment Share on other sites More sharing options...
furrybean Posted July 31, 2011 Author Report Share Posted July 31, 2011 Cheers Kent, I was just wanting to fireform this brass but I reckon some of the rubbish group was down to the heat haze (I hope!) Im keeping my fingers crosed that the brass should now perform as I want and get down the group sizes. As you said, the grouping as is are going to be okay now for what I want to gun for but not where I want them to be ultimately Link to comment Share on other sites More sharing options...
furrybean Posted August 2, 2011 Author Report Share Posted August 2, 2011 Dont suppose anyone has a neck turner and expander mandrel I can borrow? lol Link to comment Share on other sites More sharing options...
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