30-06 Load with Speer 170 Grain DeepCurl bullets a tad short?

[Bravo4]

Question for the master reloaders here since I'm a beginner at this.

Loaded 30-06 Springfield with Speer 170 Grain DeepCurl bullets, these bullets have a cannelure and when I measured the Overall length of the cartridge I got 2.931 inches, and the SAAMI specs have a Minimum overall length of 2.940 inches.

The question is: Should I just forget about this bullets for the 30-06 or would they be fine to shoot even when the overall length is just a little short ?

I know this bullets are designed more for the 30-30, but I got them on a 'sale' and calculated loading it with 45 grains of IMR 4895 would give me a tame load of about 2500 - 2600 feet/second initial muzzle velocity.
I want to use this bullets for target practice only! No hunting with them.

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[orygun]

Because this bullet is for a 30-30 the cannelure may be a bit farther up the bullet than if it was a bullet for a 30-06. If that's the case, the bullet will intrude farther into the case, eating up a little capacity. That's also the reason your OAL doesn't measure up.
Keep the powder charges on the low end of what you would for a "normal" 30-06 bullet and it should be fine.

 

[deadshot2]

If the OAL is all that "short", don't expect great accuracy. The bullet will have a greater distance to travel before it gets to the lands which will affect both how straight the bullet enters the bore as well as "barrel timing".

If they were my bullets I would ignore the cannelure and load the bullets so the base doesn't extend into the case beyond the neck/shoulder junction. Try loading a dummy cartridge with an OAL of 3,300 then see how it chambers. Also look at how much bullet you have in the neck. If the bullet isn't being engraved by the rifling when chambering the OAL isn't too long. Now just start low and work your load up. In a non tube magazine rifle there is no requirement that you crimp into a cannelure. Neck tension should hold the bullet in place adequately.

 

[orygun]

The bullet will have a greater distance to travel before it gets to the lands which will affect both how straight the bullet enters the bore as well as "barrel timing".

Try loading a dummy cartridge with an OAL of 3,300 then see how it chambers. Also look at how much bullet you have in the neck. If the bullet isn't being engraved by the rifling when chambering the OAL isn't too long. Now just start low and work your load up.

Can you explain what "barrel timing" is?

I believe that the second part is good advice, but due to the shape of the nose of the bullet (shorter ogive) I don't think you cold get away seating that bullet so far out without jamming it into the lands. You seem to be very good at explanations, maybe this would be a good place to explain how to check this. (I understand, but I think it would fill the page by the time I got done trying)

 

[deadshot2]

Can you explain what "barrel timing" is?

I believe that the second part is good advice, but due to the shape of the nose of the bullet (shorter ogive) I don't think you cold get away seating that bullet so far out without jamming it into the lands. You seem to be very good at explanations, maybe this would be a good place to explain how to check this. (I understand, but I think it would fill the page by the time I got done trying)

Barrel timing is the the time it takes the bullet to transit the barrel and leave at the optimal point of the barrel harmonics. Powder charge adjustment is the "Coarse Adjustment" which increases or decreases the bullet speed. OAL is the fine tuning. A longer OAL will mean less time in the barrel albeit by only a microsecond or several but enough to have the bullet leave when the barrel is in the same point of it's oscillation, each time.

In order to determine how far out you can seat the bullet, there are a couple of ways. One would be to buy the Hornady OAL gauge/tool with an appropriate test case. Another is simple and cheap and there are two sub-methods. One of them is to take a fired case and only size it enough to squeeze a 1/16th if an inch or so at the case mouth. Just enough to hold a bullet but not so much you can't press it into the case with some firm finger pressure. Seat the bullet so it's barely in the case then chamber this test round. When the ogive of the bullet contacts the throat/rifling it will then push the bullet into the case. When you are ready to remove the test round carefully open the bolt and using a cleaning rod, push on the bullet top while pulling back on the bolt. This will help free the bullet from the throat if it is forced into it and sticks. Then measure the OAL of the case/bullet. Subtract a suitable amount for "jump" and you have a new OAL for loading these bullets to. The second method would be to fully size a case and then take a jewelers saw or dremel cutting disc (thin) to cut a couple of slits in the neck. These slits will allow the bullet to be held firmly in the case yet loose enough to slide easily when it contacts the beginning of the rifling.

For "jump" I personally like a minimum of .020". Regardless, be sure to work up your load rather than just starting high as bullets close to the lands can cause some unsafe pressure spikes.

Now I have to go up and do this same task with my 30-06 only I already have the Hornady tool for the task. I do this every time I change bullets in any of my rifles, just to make sure I don't end up with too great an OAL unless I'm loading "Tactical" loads which are always magazine length.

 

[orygun]

Thanks!

I use the "sooting" method to check land contact, but I think next time I'll try one of these ideas. Seems like it may be easier, and more consistent.

 

[Bravo4]

Thank you all for your responses, I've loaded only 5 cartridges so far. In the next batch I will ignore where the cannelure is and will try to get a OAL of 3.3 inches as suggested.

 

[salmonriverjohn]

Thanks!

I use the "sooting" method to check land contact, but I think next time I'll try one of these ideas. Seems like it may be easier, and more consistent.

What he said, This morning I loaded up 300 rnds of -06 165's. The die used is set up for my old model 70, I use this die for this rifle only, as it's adjusted out to where it works best for this particular rifle. Remember that chamber throat dimensions vary from rifle to rifle and the ogive will vary between bullet types . So when you fine tune your die, either allow for a common one size fits all load or one that is set for a particular rifle.