Help with Trigger Safety Block and or Reloads

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Jacko
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Help with Trigger Safety Block and or Reloads

Post by Jacko »

I am not sure if this is a mechanical fault with my 45.70 Rio Grande or a fault with my Reloaded Cases. Some Cartridges Fire and others don't because the Trigger Safety Block does not fully depress, sometimes if I slam the Lever home or squeeze it real hard they will Fire. It feels as though the Cartridges are not dropping fully into the Chamber ???

Something tells me it's my reloads but I just am not sure. I have never and will never buy factory Cartridges for this Rifle. I have been reloading for a number of years so have a grasp of reloading procedures and have never had any other issues

I have checked, double checked and then triple checked my hand loading procedures and I am confident they are well within spec. I use 2 different types of projectile, a .459 commercial hardcast and a Lee 405HB [ .460 ] The Cases loaded with Lee Proj are most often the Cartridges which will not fire due to the Trigger Safety Block not being fully depressed but it does occur with the commercial Cast Bullets also. The Lee Proj do bulge the cases slightly but they seem to chamber with finger pressure. I use Lyman Dies so the M Die does expand the neck some before I seat the proj

I made up some more dummy rounds with a number of types of 45.70 proj I had lying around last reload session to double check things and they all seem to chamber and the hammer drops with no issue's with the Trigger Safety Block. Whats the point of the Safety Block ? just seems to be something else to go wrong

The Rifle functions flawlessly when I just work the action with no cartridges. The Trigger Safety Block Spring is firm but not overly so.

I did have an issue with light hammer strikes when I bought the Rifle but had it repaired under warrantee, the Rifle is well out of warrantee now but has only fired 3 or 400 rounds

I have little Firearm mechanical experience so am hesitant to dismantle the Rifle - any clues on what the real issue is. Don't want to pay the Gunsmith either, all advise taken aboard.

regards Jacko
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Re: Help with Trigger Safety Block and or Reloads

Post by donhuff »

Gday Jacko,

I try to help you figure out what going on with your Rio.

The trigger block keeps you from pulling the trigger unless the lever is in the full up position. I know that you know that part of it, but if it were not there, and you did not have the lever in the full up position (like when your reloads do not chamber completely) then a couple of bad things can happen. First, the cartridge is not full chambered. It wont be out much, but sometimes even a little is not a good thing. Second, the locking bolt will not be fully engaged into the bolt cuts. You really don't want that to happen!! Looking at the lever, and the part of it with the hook like shape to it. Then the flat part below the hook part, this is what pushes the locking bolt up and into position. The hook is what pulls it back down. While holding the gun upright in a firing position. Look at the part in the receiver that this part of the lever touches. That's the locking bolt bottom "hook. Now while holding the lever open just to the point to where it starts to move the bolt, flip the gun upside down and you will see the locking bolt "fall" to the top side of the gun and almost into position in the bolt. It usually has to be pushed up by the lever to get fully into place. Also if you hold the lever open in that position and turn the gun back over to right side up, you'll hear the locking bolt fall back to the down position (unless you have too much grease in it holding it in place).
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My 45-70 had the same issues with my reloads. I'm casting the Lee 457-405F. And I also size to .459". Some would chamber and some would not. I colored the nose of a couple of bullets with a sharpie and chambered them and push the lever until they went all the way home. I then could see that the nose of the slugs was hitting the rifling. The Rossi has a very short leade and the leade diameter is not very big either. RD sez that it is cut really close to the SAAMI specs. http://www.saami.org/pubresources/cc_dr ... rnment.pdf

As you can see there. There aint a lot of room. That tiny little shoulder on the bullet I cast is about all that will fit. And if you'll notice, most all bullets made for the 4570, have tiny shoulders or none at all. Also, the leade is very short/steep too, compounding the problem. It makes for good accuracy they say, but not so good feeding in a LEVERGUN.

So I had to seat my bullets deeper into the case to get them to chamber without resistance, or change nose shapes to something slimmer up front. I could take a couple of .001" off of the nose diameter and all was well. (if wish I could make bullet molds!). So if I crimp on the front of that forward driving ban, all is well. I also had problems with the Lee mold dropping slugs that were a little out of round, usually cause I had let a tiny drop of lead get between the two halves. This would make a bullet that would not chamber well cause it was touching the throat on two sides but not the other sides.
I have started powder coating my cast bullets, and just the thickness of the coating on the nose is giving me problems with chambering a round. I need a bullet with a smaller diameter nose I guess, but I would really like to make the leade and throat a little longer so the gun would not be quite so picky. I hesitate to cut the gun though as it is so accurate like it is right now. I'll try a different mold one day!

Also, when crimping, make sure you are not bulging the case below the crimp. I did that one too as the Lee bullet does not have a very deep groove in it, and I like a heavy crimp. I Need a different mold again! I checked for this the same way by painting the case with a sharpie. Paint all the way down to the bottom of where you can see the base of the bullet. This will tell you if your chamber is tight on your .459 bullet. Some brass is thicker than others and will so this while other brass will not. Mike the OD of your loaded round and you'll be surprised at the difference. Sometimes it only takes a half thousands to cause a problem.
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Re: Help with Trigger Safety Block and or Reloads

Post by Ranch Dog »

I can only mirror Don's comments. If your reloads are not chambering and it seems you have identified it to the Lee bullet, you do not want the trigger causing the bang as the rifle will be firing out of battery.

The RG4570 has a SAAMI spec chamber and barrel. When I first bought mine, I bought a chamber reamer so that could make the rifle like my Marlin 1895s. After spending the 200 bucks for the reamer, I thought "what the heck am I doing?" I've always cussed Marlin for their out of spec chambers and now that I had one I wanted to make it like a Marlin? Something is really wrong with that thought process!

You could dramatically improve the performance of the troubled bullet by sizing it to .458". If you are going with Lee equipment, that is not a standard size so you would need to special order it. Also, buckshot on castboolits makes the Lee style sizes for a couple of bucks less.

You can use the trouble making bullet to determine the OAL that it needs. With the rifle empty and the bolt closed, stick a cleaning rod down the barrel and mark it at the muzzle with a fine permanent marker. Next open up the bolt and carefully drop a bullet in the chamber. Give it a gentle shove with anything that will fit so that it will remain in place. Mark the cleaning rod at the muzzle with it resting against the bullet. Use the cleaning rod to push the bullet out of the chamber. Now, carefully measure the distance between the two marks. This is the OAL that will barely chamber the bullet with the bolt closed. I personally take, .005" off the measurement for a start. If your brass doesn't match the crimp groove on the bullet and you are set on using the bullet, you will need to trim the brass to match.

Back when I started with this rifle using my TLC460 bullets, I was amazed at the change in OAL when moving from a .460" bullet to a .459" bullet. A little math with another .001" change against the ogive convinced me I would see a normal OAL with this cartridge so I special ordered a .458" Lube & Size Kit. Been using a 2.500" cartridge OAL since, trimming with a standard Lee trimmer. Everything is as it should be.
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Re: Help with Trigger Safety Block and or Reloads

Post by Jacko »

Thankyou for the detailed reply Fella's you have made things very clear to me and given me a big shove in a direction I was getting too all to slowly

I am not set on using the projectiles I have been , the Mould was cheap and the commercial hardcasts where given to me. Last Thursday I ordered a Cast Bullet Engineering 458400 plain Base Mould. David cut it same day and posted it Friday. It is similar in profile to the RCBS Projectile, it is a lot shorter from Crimp Groove to Metplat than the Lee Projectile. I was seating the Lee Projectile ahead of the Crimp Groove, I will pay attention to seating depth with the CBE Projectile.

Last Friday I ordered a Lee .457 Sizing Die plus some other goodies. I planned to hone the sizing Die out to .458. I will have to be a little patient as I had to order this gear from the USA so it will take a couple of weeks to arrive

I have a Lee Case Trimmer and have been using that but also a Lyman mini Lathe type Trimmer so I will have no trouble trimming Cases to an appropriate length once I follow advise and determine what I need.

I now have concerns about the CBE Projectile, we'll see. It should arrive at work this morning so I will Cast up a few Projectile this evening and put together some Dummy Rounds. Hopefully the Mould will drop round .458 Projectiles so I can at least determine if it will not give me the same issues

I'd say I've been a bit lazy and loading Brass that fit SAAMI and not my Rifle or perhaps been lucky with reloading my other Rifles and stumbled upon a combination that worked so had a false sense of confidence. Perhaps I should have done a chamber Cast back when I bought the Rio Grande, may have avoided a few pitfalls.

Will report the results soon

regards Jacko
"To my deep mortification my father once said to me, 'You care for nothing but shooting, dogs and rat catching, and you will be a disgrace to yourself and all your family.' "

-Charles Darwin
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