10mm XTP in Colt Delta Elite- setback issue

[crimsoncomet]

Hey guys. I am trying to load some hunting/SD ammo for my delta elite. I have tried 165gr sierra hp and they will not feed at all. The bullets nose is just to square. I had heard that the XTP was designed to feed in semi-auto's, so picked up a box of 155gr XTPs. I want to push the bullets to 10mm levels. Meaning over 1300 fps. I loaded up a dummy round last night and tested it in my gun. OAL was 1.260" and the crimp was .423". It chambered easily and had no set back. I then extracted the round and chambered the round from releasing from slide lock. It only set back .001". After the second chambering, the round was set back .004". I then increased the crimp to .421" and it seemed to help some, but did not keep the bullet from setting back. I have some Double Tap 165gr golden sabres and I noticed that they are crimping there 10mm to .415". Would it hurt for me to try to crimp this much and try to defeat bullet set back? Thanks in advance.

 

[Walkalong]

.004 is nothing to worry about, and one reason it is generally recommended not to chamber and rechamber ammo.

Crimp in an auto round like 10MM is to remove the bell, not to hold a bullet. Neck tension holds the bullet. You can try loading a dummy round with sizing and no expanding. If this cures it, you need to polish the expander down some.

 

[ReloaderFred]

A powder that fills the case and is slightly compressed will also help with setback, but as Walkalong pointed out, neck tension is what gets it done.

Both of my Delta Elites feed just about anything I feed them. You might look at your feedramp and see if it's polished or rough.

Hope this helps.

Fred

 

[loadedround]

I have to agree 100% with ReloaderFred regarding my 2 Delta Elites feeding anything I feed them be it lead or jacketed bullets. My 2nd Delta is a new SS model and have only had 200 rounds through with perfect feeding. One of the best loads I've worked is a hard cast 175 gr SWC over a healthy dose of BlueDot. Excellent grouping and no leading. I use Laser Cast bullets by Oregon Trail.

 

[crimsoncomet]

Thanks guys. Maybe i am not getting the neck tension i need. The sierras were no hope at all. They jammed straight into the feed ramp and that was it no matter how short they were. I dont really see where the brass looks "rubber banded" around the bullet like some of my reloads.

If my feed ramp needs polishing, any instructions on how to do it?

 

[Otto]

Take a completed round and press the bullet nose against your bathroom scale. If you can put more than 45 lbs on the bullet without setback...you're good to go.

I wouldn't polish the chamber. The walls of a fired casing expand against the inside of the chamber and seals it. Polishing can effect the sealing and may cause the gases to blow back past the case.

 

[ReloaderFred]

Deleted

 

[crimsoncomet]

ReloaderFred and Otto,
That was my mistake in the reply. I put "chamber" instead of "feed ramp". Thanks for everyones replies!

 

[crimsoncomet]

So, I mic'd my brass after sizing at .4191" and then after seating at .4257". Seems that there is not enough neck tension. Although the factory double taps move about .004"-.006" when chambered as well.

 

[crimsoncomet]

I am still having the set back issue. .002" on the first chambering, then another .002" and so on. The round itself fits the chamber perfectly. I took my expander down a bit, and that still didnt help. What do you all think about using a EGW undersize die to increase neck tension? Thanks.

 

[918v]

Crimp does not increase case tension on the bullet.

If you get a "U" die and only minimally flare the case mouth without expanding the case itself your setback problems will be minimized. You will never get rid of it entirely, but you can manage it.

 

[gamestalker]

I load with slow burning powder's, so set back is probably being managed in part by that. I notice a very small amount with the XDM from time to time with brass that has been reloaded a lot, but it's always very minor and won't set back more than once. I'm guessing probably because the powder won't compress any more? You might try minimizing the belling to just enough that shaving isn't a problem. And if you don't mind 10mm magnum velocities, go with a super slow burning powder, that'll pretty much eliminate further issues with set back. If that doesn't work, I'm not sure what will.

 

[crimsoncomet]

Thanks for the replies fellas. I am going to be using AA #9. I am putting the minimum flare that i can on the case and it still occurs. I hope this die solves some of the issues. I wouldnt mind .002" set back on the first chambering, but I would like that to be it. Just in case i need to clear the gun and then load it back up. I guess i will just have to live with it.

 

[Sevens]

Hey Crimsoncomet, what is the brass you are using?

Any chance that you are using R-P brass, or even worse, nickel R-P brass?
It's been my experience that R-P pistol brass is some of the thinnest in the industry and while you can feel it in the press lever at both mouth flaring and bullet seating stages, you can really experience in 10mm when you pair of that brass with bullets that are on the slim side.

For me, the bullets that gave me real grief with case mouth tension in 10mm were Nosler bullets. I used 750 of their 150 grain bullets.

Terrific bullets! But in 10mm, best used with brass that is NOT R-P, or worse, nickel plated R-P. And the bullets seem to be on the thin side -- and when I say thin, I'm talking maybe a few ten-thousandths here... enough to notice when combined with thin brass.

Just to be clear, I loved the Nosler 150gr 10mm bullets and found them to be very accurate and that they made great ammo. But, they seemed just a touch slimmer than some other .40 cal jacketed slugs I've worked with.

Cast bullets are fine in the thinner Remington brass, and that's where I use most of my R-P stamped 10 brass.

So I recommend that you experiment with other brass if you have been using R-P brass. And I will second (or third) any comments that suggest you cannot fix this problem with more taper crimp. (you can't)

 

[crimsoncomet]

Thanks sevens! I am actually using starline brass, which i have heard people love for the 10mm. I have some nickel plated stored away and some plated and lead moly bullets to load in the thin brass R-P. I ordered a U die. Should be here next week. I will see if this helps. Any experience with starline 10mm?

 

[Sevens]

I have actually NOT loaded Starline in 10mm... but I have a good reason:

I don't have a lot of it, so that which I do have, it's in a jar. I'm using the brass that I've been using and collecting the few pieces of Starline that I get. When I lose or kill off my current stuff, I'll dip in to the Starline when I need to.

These days I'm shooting Precision Delta 180 grainers, I'm hoping to test some Zero 180's next.