RotoMetals2Inline FabricationWidenersLee Precision
MidSouth Shooters SupplyTitan ReloadingRepackboxADvertise here

Page 1 of 3 123 LastLast
Results 1 to 20 of 47

Thread: Light loads causing difficult to open bolt? First time out with Ross 1905E

  1. #1
    Boolit Buddy
    Join Date
    May 2016
    Posts
    269

    Light loads causing difficult to open bolt? First time out with Ross 1905E

    Good Morning Fellas,
    I encountered something I haven't experience before while shooting and I thought i'd share and see if y'all have ever encountered something similar or have some insight.
    I picked up a Ross model 1905E in .303 British and loaded up some of my cast for them. boolit is a NOE 311-180-RF (K31), i've got them sized to .314 which is exactly the groove diameter, it's what i've got available so I decided to see if it would work. I've got them above 11.5gr of Red Dot and a CCI #34 primer.

    Upon firing the bolt was very hard to open, had to bring the rifle down and hit it pretty hard with the edge of my hand. These rifles are a bit infamous for lacking primary extraction, but they definitely shouldn't be having this trouble.

    Upon examining the brass the primer was quite noticeably protruding. Definitely not flattened in the slightest, very much rounded. I decided to fire 4 more, similar results although the degree of protrusion varied as did the difficulty in opening the bolt, although a very firm hit was required in all cases. I measured the protrusion to be over .010" from flush on a couple of the pieces. Some pictures are included for your consideration.












    Thoughts?
    I'm leaning towards being far from a dangerous pressure situation, in fact the opposite being the problem and increasing my charge of Red Dot by a grain to see what happens. But i'm also curious if there's something else that could have caused the primer protrusion and how exactly it would lead to the bolt being so hard to open before I proceed.
    Or just if anyone has experienced similar on any other rifle.

    Maybe the magnum power primer contributed? I've standardized on the CCI #34 for everything I load.


    Of slight interest you can also see how the shape of the shoulder has changed after firing. I doubt that's related, and it's typical for these particular rifles but I guess i'm going to neck size from here on out.


  2. #2
    Boolit Master
    Join Date
    Oct 2013
    Posts
    769
    that's normal for low pressure, everythime you fire the primer backs out because that's where the pressure starts, shoves primer back and case forward kinda wedges like that, then normally the case would make even more pressure and send the case back over the primer seating it flat again. theres a thread on what size drill bit you can drill the flash hole with to make it not happen. ill add it if I can find it

    you can google to it, cast boolits is drilling out flash holes dangerous
    Last edited by bmortell; 11-18-2019 at 07:31 AM.

  3. #3
    Boolit Master
    Join Date
    Nov 2017
    Location
    brisbane ,qld,australia
    Posts
    997
    I had increasingly difficult extraction with a Ross 303 and light loads/lead cast..........found out what I was doing was putting a small ring in the chamber,caused by the fast powder.....I had to lap the chamber ,not to eliminate the ring,but to remove any areas where the brass cases were dragging .......to do this I used 30/30 cases ,with fine (400 grit) lapping compound.

  4. #4
    Boolit Master

    Join Date
    Mar 2011
    Location
    oklahoma
    Posts
    1,679
    With a hard to open bolt, I'm wondering I'd there is setback on the lug abutments from previous high pressure loadings. a protruding primer shouldn't cause a hard to open bolt.

  5. #5
    Boolit Master



    cwlongshot's Avatar
    Join Date
    Jul 2012
    Location
    Central Connecticut
    Posts
    2,004
    Its a slight head space issue. Probably one you created by moving shoulder back when resizing.

    As mentioned, The case is moved forward in the chamber and upon firing the primer is pushed out with pressure. But because pressure is light, the case isnt set back to re seat it. Not super uncommon. Not dangerious either.

    I was forming some 6.5/06 using starting loads and a 130 Sierra J bullet. The brass was formed from 30/06 then annealed and loaded. I had very hard bolt lift. Mine was determined to be soft cases as my load was cery light and this gun allowes long seated bullets so max advertised loads are never hot in it.

    CW
    NRA Life member • REMEMBER, FREEDOM IS NOT FREE its being paid for in BLOOD.

  6. #6
    Boolit Grand Master


    Larry Gibson's Avatar
    Join Date
    Jul 2005
    Location
    Lake Havasu City, Arizona
    Posts
    17,882
    Drilling out flash holes is the solution along with neck sizing the cases. I use cases with the flash holes drilled out with a #30 drill in my Ross M10 which was giving me similar problems. I suggest a #30 to not larger than a #28 drill.

    Drilling out the flash holes is not dangerous. I conducted an extensive test using such cases in the .308W measuring the pressures and velocities with low cast bullet loads all the way up to full loads with jacketed bullets. Actually with light loads of faster burning powder such as you are using the larger flash hole will give more consistent ignition. Reading all the test results through out the thread will give you a good under standing;

    http://castboolits.gunloads.com/show...oles-dangerous
    Larry Gibson

    “Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
    ― Nikola Tesla

  7. #7
    Moderator


    ShooterAZ's Avatar
    Join Date
    Jan 2012
    Location
    Flagstaff, AZ
    Posts
    7,226
    Drilling the flashholes is the solution. Continued firing of light loads will eventually lead to headspace problems due to the shoulder being set back by the primer thrust.

  8. #8
    Boolit Grand Master

    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    5,051
    Neck sizing should cure this problem for you, a Lee collet neck sizer sounds to order. Even though this is a rimmed cartridge that is supposed to head space off the rim the chambers are large sized for extreme field conditions. Neck sizing will make you brass last longer by a large margin and allow you to head space off the shoulder like a rimless cartridge. As ShooterAz suggests drilling flash holes will help keep the shoulder where it should be.
    Hell, I was there!

  9. #9
    Boolit Master



    cwlongshot's Avatar
    Join Date
    Jul 2012
    Location
    Central Connecticut
    Posts
    2,004
    Neck sizing is ONLY an option if you know you have properly fireformed cases. These cases ARE NOT! We know this because the primers where un seated.

    CW
    NRA Life member • REMEMBER, FREEDOM IS NOT FREE its being paid for in BLOOD.

  10. #10
    Boolit Grand Master



    M-Tecs's Avatar
    Join Date
    Apr 2008
    Location
    Minnesota
    Posts
    5,898
    It's a low pressure side effect. You have at least workable three solutions. Increase the pressure enough that the primers reseat, use O-rings on the case or as Larry suggested drill the flashhole. The 303 headspaces on the rim but the issue is the primer force pushing the case forward. Neck sizing may or may not work depending on pressures. Magnum primers generally makes this side effect more pronounced.

    Some great info on drilling primers here http://castboolits.gunloads.com/show...oles-dangerous
    Last edited by M-Tecs; 11-18-2019 at 07:43 PM.
    2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."

  11. #11
    Boolit Grand Master

    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    5,051
    Quote Originally Posted by cwlongshot View Post
    Neck sizing is ONLY an option if you know you have properly fireformed cases. These cases ARE NOT! We know this because the primers where un seated.

    CW
    1-Load them up enough to reseat the primers, then neck size.
    2-Neck size only and load hotter until primers reseat, then NK size only
    3- expand the necks to 35 caliber, size back until you can just chamber a round with slight resistance, creating a false shoulder and zero head space, after this firing NK size only
    Hell, I was there!

  12. #12
    Boolit Master
    Join Date
    Dec 2009
    Posts
    4,615
    Quote Originally Posted by bmortell View Post
    that's normal for low pressure, everythime you fire the primer backs out because that's where the pressure starts, shoves primer back and case forward kinda wedges like that, then normally the case would make even more pressure and send the case back over the primer seating it flat again. theres a thread on what size drill bit you can drill the flash hole with to make it not happen. ill add it if I can find it

    you can google to it, cast boolits is drilling out flash holes dangerous
    Had the same problem with light loads behind a standard 158 gr bullet in a Colt .38 Special.
    Later when using an even lighter load behind a round ball a S&W Airweight functioned with no drag at all. I suspect the very light RB load didn't build enough pressure for the case to expand much if any.

  13. #13
    Boolit Master uscra112's Avatar
    Join Date
    Jun 2006
    Location
    Switzerland of Ohio
    Posts
    3,330
    GUYS, it's a rimmed cartridge! Just think about that for a moment.

    BTW that primer protrusion is a measure of your headspace.

    And Quickload says that 11.5 grains of Red Dot is producing something like 32,000 psi with that weight bullet. Not exactly a pipsqueak load.

    Based on what's been posted, I'd be looking for a rough chamber.

    I wouldn't rule out the lug abutment setback possibility either. That plus rough chamber would make the bolt lift hard. As the bolt is opened, it has to move forward to get out of the "pocket" in the abutments, but the case doesn't want to move with it.

    Slower powder would get you the velocity you want at lower peak pressure. That might alleviate the problem until you can get the chamber polished. Something in the range of AA1680 or RL-7 or H4198. I've read of guys using around 30 grains of Varget in the Krag case for cast bullets in that weight range. Quickload says pressure would be just over half of what you're getting with Red Dot.
    Last edited by uscra112; 11-19-2019 at 04:48 AM.
    flectere si nequeo superos, acheronta movebo

  14. #14
    Boolit Grand Master



    M-Tecs's Avatar
    Join Date
    Apr 2008
    Location
    Minnesota
    Posts
    5,898
    I had very good results with Ed Harris "the load" using 13 grains of Red Dot.

    https://www.hensleygibbs.com/edharri...The%20Load.htm

    http://castboolits.gunloads.com/show...nd-303-British
    2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."

  15. #15
    Boolit Master uscra112's Avatar
    Join Date
    Jun 2006
    Location
    Switzerland of Ohio
    Posts
    3,330
    And with a gun that doesn't have any wear&tear issues you wouldn't. I've fired enough myself to know, although I eventually quit with the Red Dot and started using a lot of the powders I mentioned, (except I never have tried that Varget idea. Health has kept me from any ranges longer than my back yard for nigh on four years now. )
    flectere si nequeo superos, acheronta movebo

  16. #16
    Boolit Buddy
    Join Date
    May 2016
    Posts
    269
    Alright, so I pulled the rounds I loaded and tried again.
    I loaded 5 up with 13.0gr of Red Dot. The primer protrusion was as expected much less noticeable. As you may have noticed i'm using mixed brass, and I noticed that the force required to open the bolt varied from headstamp to headstamp. The RP seem to take the most force, and I had one single Dominion headstamp in there and it extracted with no force at all! I processed all my 303 brass as one lot, same sizing/trim length, everything. This could be a red herring?

    I'm 10 min from the range so I went back home and loaded up 5 more, this time with 14.0gr Red Dot. Extraction was as problematic as ever. Primers are pretty close to flush now though so we might be dealing with unrelated factors here.

    I'm running cast in a half dozen rifles and almost as many calibers without many problem. I was really looking forward to getting this rifle shooting since I have cosmetically nice Mk.III Ross that is very nice except for the last two inches or so of rifling being worn right out and giving poor accuracy. I snapped this rifle up since the bore was good (and it's MUCH lighter) so I could get some Ross fun in and use up .303 brass I have lying around to throw some cast.


    Quote Originally Posted by uscra112 View Post
    GUYS, it's a rimmed cartridge! Just think about that for a moment.

    I'm thinking about it. What are the implications?

    BTW that primer protrusion is a measure of your headspace.

    And Quickload says that 11.5 grains of Red Dot is producing something like 32,000 psi with that weight bullet. Not exactly a pipsqueak load.

    I'm using Red Dot in a few different calibers with great results. I'm curious what quick load would say about 14 grains of Red Dot, actual mass of the boolit is 192gr. with the gas check. Lyman Cast manual has loads listed in Red Dot in many calibers, but they never give pressure data. I'm in the range i'd be cautious going higher, for sure.


    Based on what's been posted, I'd be looking for a rough chamber.

    That's something i'm considering as well. Looking at the chamber it does not appear rough though, no pitting or rust that I can see. What could I do on this front?

    I wouldn't rule out the lug abutment setback possibility either. That plus rough chamber would make the bolt lift hard. As the bolt is opened, it has to move forward to get out of the "pocket" in the abutments, but the case doesn't want to move with it.

    Here's a bit of extra info for you. First thing's first, this rifle is a straight pull, so we don't actually have a "lift" component to opening the bolt. But after firing I can move the bolt a fraction of an inch back, and see the lugs start to rotate out of battery, until I hit a wall. It seems more likely to me the lockup is very smooth, and I run into the resistance at the point where the lugs are partially unlocked and you're starting to actually pull the case out of the chamber.

    Slower powder would get you the velocity you want at lower peak pressure. That might alleviate the problem until you can get the chamber polished. Something in the range of AA1680 or RL-7 or H4198. I've read of guys using around 30 grains of Varget in the Krag case for cast bullets in that weight range. Quickload says pressure would be just over half of what you're getting with Red Dot.

    I'm not after velocity at all. I would indeed use up some of my Varget or H4895 at around 30 grains, i've done that in other calibers/rifles with good result. I in fact was strongly considering trying 30grains of H4895 or more to see what would happen tonight but didn't feel like driving to the range for the third time. Great post,thanks for your thoughts
    Last edited by Peregrine; 11-19-2019 at 07:31 AM.

  17. #17
    Boolit Master
    nekshot's Avatar
    Join Date
    Nov 2008
    Location
    swmissouri
    Posts
    3,027
    I have nothing to ad to what advice is given, but I kinda envy you with that rifle! Problem and all I would be happy with it because you will get it figured out!
    Look twice, shoot once.

  18. #18
    Boolit Grand Master

    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    5,051
    14 grains of Red Dot is too hot with that bullet. You now have the 5 cases from that loading that are fully fire formed though. I would neck size them only, drill the flash holes, load with your original 11.5 grain RedDot and fire. If this solved your extraction problem you know how to fix the rest.

    EDIT:14 grains of Red Dot is too hot with that bullet. This is my opinion only. I do not have Quick Load to ESTIMATE time/pressure
    Last edited by swheeler; 11-19-2019 at 12:46 PM.
    Hell, I was there!

  19. #19
    Boolit Master uscra112's Avatar
    Join Date
    Jun 2006
    Location
    Switzerland of Ohio
    Posts
    3,330
    Quick and incomplete answer. 14 grains of Red Dot calculates to 44,000 psi in the model, assuming I have guessed the seating depth correctly. The peak comes just about .23 milliseconds after ignition, which is very quick. Calculated velocity 1700 fps. Contrast with a load of 16 grains of Blue Dot, which also yields a calculated 1700 fps, but the peak pressure is only 24,500 psi, reached at .62 milliseconds. That should explain why I switched all those years ago.

    Keep in mind that the velocity you get most closely relates the area under the pressure/time curve. Red Dot goes very high, but drops off very quickly, too. The slower powder doesn't go so high, but stays elevated longer.

    I know almost nothing about the Ross, never having had one . But I do have two K-31s, so I'm not totally ignorant of the principles. Despite being a straight pull, the bolt still rotates to lock. That little bit of rotation you say you can see may be what is necessary to take up lost motion before initiating primary extraction?

    This is all hypothesis, of course. I could be all wet, but I can't think of anything else that explains what you've described.

    I'd try thinly coating a case with magic marker ink, firing it with your 11 grain load, and looking for indications that it's dragging during primary extraction. That would definitely show if you've got a ringed chamber. If it's not, then write off the hypothesis and look elsewhere.
    flectere si nequeo superos, acheronta movebo

  20. #20
    Boolit Grand Master

    swheeler's Avatar
    Join Date
    Mar 2005
    Location
    Montana
    Posts
    5,051
    Drilling out flash holes is the solution along with neck sizing the cases. I use cases with the flash holes drilled out with a #30 drill in my Ross M10 which was giving me similar problems. I suggest a #30 to not larger than a #28 drill.
    I believe Larry

    As to the 14 gr of RedDot with 192 gr bullet, too hot is my opinion, you can shoot as many of those as you want.
    Hell, I was there!

Page 1 of 3 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check