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Catch-22

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About Catch-22

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    Newport - sunny South Wales

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  1. Inconsistent Neck Tension.

    Oh and to fine tune your loads, you'll need to play around with seating depth. use the OCW method (if you aren't already) to find a nice consistent powder charge node and then play with seating (bullet deeper or shallower in the case) to find what works best. You may find bullets like to be jammed into your lands or jumped into them. You may also find you need to try a different powder or even primer, so don't discount these possibilities. As ever, good luck & happy shooting!
  2. Inconsistent Neck Tension.

    Hi Chaz loads of questions there 🙂 I'll do my best to answer. 1. I'd just not bother with the expander button in your FL die. IMO I've never had a good experience with one. Simply dissemble the die, unscrew the expander (leaving the decapping pin in place for primers). FL the brass (without expander) then use your Sinclair Expander Mandrel Die (costs about £20) 2. You say you aren't using bushings but in your first post you state you neck size the brass after you FL size. How are you neck sizing without using a neck sizing die with bushing? Have you dissasembled the neck die to see what bushing is in there? If you do find a bushing, it should have a number marked on it. This tells you the inside diameter. You can buy extra bushings and simply order 2-3, the size you want (per my previous mesuring instructions) and one size above and below. You then have a number of possible tensions to try. BUT...tbh, I just wouldn't bother neck sizing. Use the FL die then the expander mandrel die. 3. So what happens with a sizing die with internal expander is the brass enters the die, the expander forces the neck open, then the neck is reduced (either with bushing of neck sizing or a 'standard' amount if FL sizing) and primer removed. Drawing the brass out now pulls the expander back through the neck opening it up again. But it's this pulling which can both stretch the brass but also get things out of whack. Using a dedicated Expander Mandrel die, the brass has already been sized and neck diameter reduced. As the brass enters the Expander Mandrel, the calibre specific Mandrel opens the neck. Drawing the brass out of the Expander Mandrel doesn't do any further sizing or pulling on the brass as that was done on the 'down' stroke of the press. Expander Mandrels also use a floating mandrel, so it self centres which aids a more concentric sizing operation. using a neck sizing die together with an expander mandrel doesn't make sense. If you think about what the neck die does (reduce neck diameter by a predetermined amount using the bushing size of your choice) you then just open it up again according to the diameter of the calibre specific Expander Mandrel die. Which is why I think it's best to simply ditch the neck sizing die & bushings and just use a FL die and Expander Mandrel die. 4. If you look at most shooting disciplines, you'll note most people FL size. If you're running a competition, F class, PRS etc, you want your cases to feed easily without getting stuck. NS you can't guarantee that. With FL you can. Some people will say NS your ur brass is the size of your chamber. True. But when the brass grows and expands with successive firing, you've got to FL size it anyway. Having tight fitting brass one moment then looser brass the next you can't ever know if shooting the looser fitting brass will cause a change in shot. Whereas if you FL size, you're bumping shoulder only a tiny amount but all your brass is consistently at always the same size. You can now guarantee shot to shot consistentcy because your brass will always be the same dimension. Also with FL sizing, as you're only bumping the shoulder a very small amount each time it's not really working your brass. Using the expander in your die (pushing through neck, sizing neck, then pulling Expander back through again) actually works the brass more! Admittedly, firing and sizing brass does 'work harden it' - meaning it looses its elasticity, becoming brittle and easy to break/split. Annealing is your friend here and softens the brass again, prolonging its life. This is another advanced step which probably won't be of benefit to you yet but may be something you wish to consider for the future. A lot to chew over, but for simplicity, I'd bin the neck die and only FL size then use Expander Mandrel. HTH
  3. Inconsistent Neck Tension.

    Quit with the neck sizing - just FL size. In a previous post I made the point that neck sizing pushes all the inconsistencies of the brass inwards, to the inside neck diameter, which will affect neck tension/grip on the bullets. I'd suggest getting yourself a Sinclair (or other) Expander Mandrel die. Using the Expander Mandrel AFTER you FL size will open the neck to about 0.02 undersize and it'll also push all brass inconsistencies to the outside of the neck. This will all help with improving neck tension. BTW, how are your loads shooting/grouping? Also what neck size bushing are you using? Bear in mind not all bullets by different manufacturers are exactly the same diameter. You will likely need a series of different bushings to increase/decrease the neck tension to suit your bullet/case combo. Simplest way to determine this is by using your calipers to measure a bullet (do so for each type of bullet you have), then measure the thickness of the brass at the neck mouth. Take the brass thickness measurement, times it by two (because you'll have the brass on the other side of the bullet) and add this number to the diameter of your chosen bullet. Now subtract about 0.02" (for desired neck tension). The number given should equate to a bushing size/diameter. I bet you'll get different numbers for different bullets. Again, I still believe you get the best results from giving up neck sizing! Just my opinion.
  4. International Barrels

    Has anyone used / shot a barrel from International Barrels based out of Canada? I know a bit about them but would be keen for 1st hand experience please. Cheers!
  5. new 6m br

    Yes you can use straight out the box - just load and shoot. However, to start with best consistency I do the following with all my new brass: 1. Full Length resize all my brass to minimum spec (do so without expander button) 2. Use my Sinclair Expander Mandrel on the necks. Sometimes new brass neck tension can be a bit too tight IMO 3. Take 10-20 cases, measure the length and trim all cases to the shortest one you've found. 4. Chamfer and deburr the case mouths after trimming. In the end you should have all your brass fairly consistent. Extra steps you may also want to consider are checking flashholes for burrs and ream them out. You could also ream the primer pockets so they're all the same size and depth. If you've a tight necked chamber (e.g. Custom chamber...not really applicable for a factory chamber) you may need to neck turn the bass. However I don't do any of the above because I've never needed to...and certainly can't be arsed as I'm not shooting competitions. No doubt you'll hear other opinions/experience. Happy shooting
  6. PM2 on AI NEEDS FITTING

    Absolutely. Torque down ring screws in opposites to each other to the point where you can't easily rotate the scope. Now check scope alignment and keep tightening screws down in sequence as before but now doing just a turn or two. Keep checking level between each tightening turns to ensure scope isn't rotating on you as you're making the final torquing turns. Btw, you should be torquing the scope rings and the mount to the picatinny rail appropriately. Rings: 15-25 inch pounds Mount to picatinny rail: 45 inch pounds http://precisionrifleblog.com/2013/03/22/rifle-screw-torque-settings-specifications/
  7. PM2 on AI NEEDS FITTING

    Use the wedge...the bottom of the S&B turret housing is flat, so can use the wedge against that to ensure the scope is correctly levelled within the Spuhr mount. I'd also check against a plumb line. Simple idea and requires no additional tools (other than a spirit level, though the Spuhr mounds do have a bubble in them which can be used too!). Simple vid from YouTube showing you how: L
  8. For what it's worth, I used to neck size only (Wilson dies and Arbour press) but if you think about what handloading is trying to achieve and that's completely consistent ammunition. You can't achieve that NS only because each case (as you've demonstrated) will all show slightly different dimensions after firing. When FL sizing, you're ensuring not only all your bullets will chamber without issue but they're all sized (shoulder & body) the same. This produces consistent ammo. i do however like being able to control neck tension, to perfect the grip depending on the bullets used. For this reason, I bought a set of Whidden FL dies which also NS the case at the same time (using Wilson or Redding bushings). So with the Whidden's I believe you get the best of both worlds! I must say that AFTER sizing, I use a Sinclair Expander Mandrel to open the neck. The sizing operation compresses the neck inwards and pushes any dimensional inconsistencies to the inside of the neck. This means you get variances in grip force on the bullet around the circumference of the neck. Not good! But using an expander mandrel after sizing, forces any inconsistencies outward, to the outside of the neck. This leaves the inside circumference of the neck concentric and thus grip tension on the bullet the same. Some good articles here: http://www.accurateshooter.com/technical-articles/reloading/expander-mandrels-and-neck-tension/ http://bulletin.accurateshooter.com/2017/10/stop-neck-sizing-why-you-should-full-length-size-your-brass/
  9. Link to a previous topic in which the OP had a similar issue to yours. Last post explains the diagnosis and fix http://ukvarminting.com/topic/41884-another-headspace-headache/?do=findComment&comment=326857
  10. Have you checked that the inside of the die, up top where the expander mandrel/pin screws into? I've not used Hornady dies but have experienced similar problems if the top of the die is screwed down too deeply. The brass, if slightly too long, can contact against the top of the die preventing the shoulder from being bumped back sufficiently. Worth a check first before you go buying extra stuff.
  11. I've already drafted my response and will be contacting both my MP and AM soon. However, I too agree the various organisations out there representing our community simply haven't done enough. It may be too early in the consultation phase, or there's lots going on behind the scenes that I'm unaware of, but the more I've looked to BASC (in particular) for help/advice, the more disappointed I am. It seems they're far more interested in writing mediocre drivel, cramming yet more advertising into their magazines and providing duff and inaccurate advice.
  12. Chaz, i wonder if you are looking for these videos...I posted them in the 'Handloading' section in another thread.
  13. At last a perfect afternoon for varminting

    Very nice stock - lovely grain and I like the cheek piece. It's a Tikka T3 right? Who may I ask made the stock? cheers
  14. RCBS chargemaster Lite arrived today!

    Yes it's a tricky one to answer. Different powders have different energy ratings, so one powder will give more uumph than another. Then you've got to consider not all kernels of the same powder are identical. Barrel length and even the tightness of the bore will affect pressure developed in pushing the bullet to the target. Bullet weight is another factor, lighter bullets need less effort than heavier ones. However, if you think each kernel of say VARGET could be around 1-2fps depending on the variances noted above. So if a kernel of VARGET is about 0.02gn, a variance of around 0.1gn between charges could be around 10fps. Below is taken from the Autotrickler website as he's a lot smarter than I am and does a good job of explaining how to translate the affect of accurate powder measuring into best case target scenarios. "Note that if you operate the A&D scale in units of grains, it reports in divisions of 0.02 grains. That is actually 1.3 milligrams, so it is slightly less precise. However, this is still less than the weight of a single kernel of Varget.Let's relate powder weight to muzzle velocity. I will use my competition load as a reference: 308 caliber, 185 grain bullet, 30 inch barrel, with 44 grains of Varget. The muzzle velocity is 2750 fps. The relationship between powder and muzzle velocity is 50 fps / grain. It may vary from 35 to 100 for larger or small cases but 50 is a good working estimate.That equates to 0.77 fps per milligram. This means if I add one more kernel of Varget it will increase my muzzle velocity by 1.16 fps. Now we can relate muzzle velocity to elevation at long range. For my load at 1000 yards, ballistics calculators tell us the relationship between muzzle velocity and elevation is 0.03 moa / fps. That means that one extra kernel of Varget would put that bullet 0.035 moa higher on paper.Now lets set up three scenarios for comparison: (using fictional characters that bear no resemblance to actual people!) Mr. Speedy would have us accept any charge within +/- 0.02 grains 95% of the time. This is how I recommend to use the autotrickler, because it will finish within this range most of the time and requires little effort from the user. Working in the unit system you are familiar with means you are less likely to make a mistake. Mr. Careful adds or removes a kernel by hand until the scale reports exactly the right number in milligrams. This is the best possible with the A&D scale, and what I'm sure many of us do to prepare for a national championship. Mr. Perfect settles for nothing less than absolute perfection. He reloads in an underground clean room and his powder charges have a weight error of exactly zero. If the measurement of the powder charge was the only factor that goes into the muzzle velocity variation of a load, then we would all be firing one-hole groups at 1000 yards. There are other random errors at play, most notably the combustion process itself.We have to choose a value for "everything else", and we have to work in terms of standard deviation (not extreme spread) because we are talking about normally distributed random error. The SD of a well-developed load might be around 4, so let's use this as the example.This is the point of confusion for most. How do you combine two independent error sources? They do not just add together. This is a key point to understand when applying statistics to shooting.To illustrate the concept, I like to use a chronograph as an example. Suppose your chronograph has an inherent error SD of 0.1%, which is 2.75 fps. Now you would like to measure your ammo which actually has a true SD of 4 fps. Well, whether you like it or not, if you fired enough shots and measured the SD of what you get, it will not be 4. It will not be 6.75 either. You will get an SD of (drumroll please...) sqrt(4 x 4 + 2.75 x 2.75) = 4.85. Sometimes your chrono reads high when your bullet is slow. Sometimes your bullet is fast but the chrono reads low. When all is said and done, you get the square root of the sum of the squares.So now back to our three scenarios. For the purpose of converting our weighing strategies into SD, we divide the total range by 4. Because for a normal random variable, 95% of samples are within +/- 2 SD.Mr. Speedy is okay with +/- 0.02 grains which means an SD of 0.01 grains. This is an SD of 0.5 fps. Combining that with our 'everything else' SD of 4 produces a load with an SD of 4.031 fps.Mr. Careful applies a little extra effort to weigh to an SD of 0.25 milligrams, which is 0.19 fps. This produces a load with an SD of 4.005 fps.Mr. Perfect magically produces ammo with an SD of 4.000.Now how does this relate to elevation on target? Well, for each of these loads, fired perfectly from a machine rest in completely still conditions: Mr. Speedy: 95% of shots will fall within 0.4837 moa. Mr. Careful: 95% of shots will fall within 0.4806 moa. Mr. Perfect: 95% of shots will fall within 0.4800 moa. The difference between these spreads is less than 1 millimeter at 1000 yards. Consider how much we struggle to keep the bullets within a 1 moa circle in match conditions. If you add all the other error sources like aiming, mirage, wind, and the gremlins, you can work out mathematically how little that last kernel really means.
  15. RCBS chargemaster Lite arrived today!

    The closest I've found is the Autotrickler and Autothrower system, which when combined with a Satorious or A&D scale, delivers loads to within 0.02gn (as good as I've been able to do with the CM Lite) but without any need for trickling up and only takes 10 seconds per measure. Looks great and would be really fab to use but its a step up financially - about £800 for the whole package, including scale, whereas the CM Lite is just short of £400 new in the UK.
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