O.K, first things first. please pay respect for all the cases and projectiles that were sacrificed to bring you this data
Lets get down to the nitty gritty………
taper crimp diameter at the case mouth was .472
240g XTP mag bullets
Hornady case with small rifle primer
CCI 450 small rifle mag primers
OAL 2.130″ (case mouth just below the cannelure)
45g = 2202 fps. NO pressure signs
46g = 2287 fps. NO pressure signs (case is sealing well at this point)
47g = 2367 fps. NO pressure signs
48g = 2404 fps. ABSOLUTLY NO PRESSURE SIGNS (accuracy is 1MOA)
NO feeding or extracting problems at all!!!
After returning home i drilled out the primer pocket, seated a 240 XTP to an overall length of 2.130. I then filled the case (AA1680)to the bottom of the primer hole which held 50g of powder, this would be an uncompressed load.
Now, when i used my bullet puller (hammer type) to remove the bullet it broke lose from the case very easily, i then sized the case once again and seated the bullet so the case mouth was over the cannelure (2.080″ OAL) and then taper crimped the case, i then proceeded to pull the bullet with the hammer this time it took 4 good hits from the hammer to dislodge the bullet rather than one hit.
I then reseated the bullet and measured the case capacity which was 48.5g of AA1680 with a 2.080″ OAL.
I need some help!
When i try to cycle some reloads through the chamber they are getting stuck, and i can not figure out why. I used the thunk test for the first reloads and they made a good sound when they fell into the chamber. my second reloads were ok but not as good as the first batch. This round will not eject when i cycle them i have to use a cleaning rod to tap the round to get it to dislodge Very carefully.
There is a bulge at the bottom of the bullet in the brass and i wonder if this is the problem. I have tried a few things and can not figure it out. First i tried not to use the flair die no help. I tried a heaver taper crimp but i belive that the case mouth was not seating. I tried using less taper crimp no help.
I tried resizing the loaded round but it drove the bullet deeper into the case.
If you are using longer bullets in this batch of loads, you may need to neck ream to account for the thicker brass below where you were seating before.
As usual, apply sharpie marker to the offending case and chamber it.
The sharpie marker will rub off where it’s tight.
10-4, this is great advice and you need to do as advised and get back with us. You shouldn’t need to ream, but Randal makes his point with the longer bullets.
Consider. The reason for the great accuracy with some of these loads is because Bushy holds tolerances that the competition only dreams of and it’s a possibility that your chamber is being touched by brass that is flowing, hence what Randall is trying to ascertain, with the sharpie.
Question, when you resize the loaded reloads is the bullet seater coming into contact with the bullet as you resize again, causing the bullet to be further seated down into the case, just as the taper-crimp is going on? Make sure that the re-resize step is a separate operation, screw out the bullet seater so it can’t possibly touch the bullet. Your cure is proably one of these thoughts ( if it turns out that Randal wins, then he owes me a loaded pizza and if I win he owes me two pizza’s…I love this game), once you get it and understand what’s really happening, you’ll be back in Shooters Heaven again…t
Two things — one, the reloaded cartridges are out of round. Factory stuff is pretty straight — I have had issues with concentrity (spelling) with reloads. Also, I have reloaded some of mine stuff up to 5 times. The brass does grow. Factory says OAL to be 1.7″ max. Trim to length per factory is 1.69″. This can effect crimp.
Generally speaking, if the crimp die is actually made to spec you can not over crimp, using a taper crimp die. 1.69″ is way to short, in my opinion, and is Hornady’s standard. That’s .010″ and is the standard for the 45ACP/9mm lugar (auto pistols) ect. My orginal standard to Bushmaster was 1.700″ plus nothing, minus .003″ or 1.697″ and will make your groups even more accurate (as if accuracy ever was a problem).
You really need to do the sharpie test. Close-up pics labeled 12-3-6-9 o’clock would give us a chance to see what is going on. I’m intrigued about your run-out (concentricity). How much is it? What model of press do you use?
I trimmed 100 cases last night. Before trimming, most of them varied between 1.690 and 1.697. The once fired Hornaday cases were 1.690 to 1.692. Most of the other cases had been reloaded 3 times. Seems that Hornaday is making these cases on the short end.
I am using an RCBS press w/Hornaday dies.
Well, .010″ is not really short, just more than I like. There are production realities that we’ve just got to put up with, but we as custom reloaders can hold much tighter standards. Having said all that, Hornady really has made some mighty fine accurate fodder, you must admit.
As an after thought, make sure you full length resize before you trim and then trim to the shortest cartridge you wish to use, saving the rest for other uses.
I would say not.* I admit to not having tons of experience, measured in the low four figures, with hard cast/gas checked bullets, but one time we shot 500rds and removed the gas tube for inspection and there was no tube fouling.* I have a customer that has 30+ years of shooting this style of bullet in AR’s and he, with absolutely no reservations states, that the hard cast/gas checked bullets are no problem, what so ever.* Feeding should be no problem either, as the 450b will with a great deal of reliability, not absolute, feed empty cases.Crimping?* With the lead bullets stay out of the crimping grove with the case mouth, which may mean adjusting the OAL or using a different hard cast/gas checked bullet, just stay as close to 2.250″ as possible, remember for any given load, the pressures go up the deeper the bullet is seated into the case or shorter the OAL.* For jacketed bullets, any proper made taper-crimp die cannot over crimp.* For proper ignition and to prevent any bullet travel in the case, use a heavy taper-crimp.* I personally want to see visible denting of the bullet.* Just double check your loads by removing the bolt/carrier and dropping the loaded round onto the chamber, you must hear an auditable “Thunk” when the case mouth seats against the end of the chamber.* If you don’t hear the thunk then you may have a crimp die that can over crimp (something I’ve never seen), which can give excessive head space, or the bullet has possibly caused the case to over expand (bulge) and is impeding the forward travel and preventing proper seating in the chamber.* “Carefully“, full length resize the loaded case again and that should take care of any bulge problems, be careful to clean any case lube off the cartridge, lubes in the chamber will induce excessive bolt thrust, keep those chambers dry.* Of course you could resize the bullet down a little in any of the various Luber/sizer dies (BTW – using a .451/.452 luber/sizer die and standard lubed .458 lead bullets, will lube the die just right for resizing jacketed .458 bullets down to .451 standards and you’ll end up with some really cheap lead plinking bullets to boot, just do not move them very fast or you’ll lead up the barrel.* I use one lubed lead bullet for every five jacketed bullets, there have been no jacket problems to date, heck you’re only taking the bullet down .003 per side).** If you see that your reloads do have the stated bulge do the thunk test, if you hear it, don’t fret the bulge.
I am seating the hornaday 240 XTPs to 2.017″ I don’t think the 450B has much freebore, the factory rounds only show about .025″ before they start to taper. I am loading 36.5 H110 at 1950ft/s. I am staying there because these rounds print on target the same place as the factory rounds. My groups are running abou 2″. The same as hornadays factory rounds in my gun. I don’t need more speed, I’m Happy.
I’ve re-visited using the Winchester 284 case and honestly I don’t know why I was having such a hard time the first go around, they seem to work fine.Just cut ’em off at the shoulder, trim them to 1. 995″ (I think thats the size, I’m away from my info, but whatever the factory case length is), and go. I backed off the roll crimp and used the taper crimp die. Now I just need to find out what difference the large rifle primers make with the powder I’m using compared to the factory small rifle primer. I’m headed to the range today with some progressively hotter loads to find out.