ihmsa forums

OK! Been hacking away with my Contender in 7TCU for a short while now. Accuracy with the long free-bore is, shall we say, erratic. 6" at 50 yds. qualifies as erratic I'd say. Occasional shots within 1.5" of each other, probably by accident. Good thing my Palma rifle shoots better than that! Lapua cases/IMR 4895/Tula primers. Been using Hornady 139s (Interbonds and SSTs) seating out until there is only .100" shank in the neck (that's OK, it's still a compressed load) giving a .200" leap into the lands. Have changed to Sierra 168 MKs and managed to reduce the jump to .080". We shall see. I realize that I am probably most of the problem but I have had much better fortune with other handguns than this. Open to thoughts and experiences upon the Contender barrels and 7TCU loads as well as prone technique (creedmoor style so far - hold seems steady, hair under 2Ib. trigger).
Thanks,
MIke

My opinion is this - forget about how close you are to the lands ! I have never had a TC factory barrel that would allow this anyway. My rule of thumb has been this, and has served me well - seat the bullet to the base of the neck, or to the powder level. Bullet jump does not have nearly the negative effects that some think. I would reduce those published loads also - in my experience they are VERY hot !

I have used Phillip's method for my loads and it has worked for me. Also try his suggestion of reducing the powder. Try heavier bullets instead of more powder.

+1 what Philip said about seating base of bullet to bottom of neck. TCs with long throats seem to shoot best this way. Try 24.5 or 25 grains of H322 with the 139 Hornady bullets. Max loads don't always give the best accuracy in TCUs. I had to work had to find a bad load with H322. AA2015 almost the same powder and is also good in 7TCU. 4895 is a good powder too but I have had better luck with the other two powders. 7TCU is also a great cast bullet cartridge using the RCBS 145 design bullets.

Fantastic folks, thank you!

I have had good luck with 23.5 gr. H322 under a 140 Sierra FB.

27.0-27.5 gr WW748, WSR primer, and about any bullet 139-145 has been "the" load for many IHMSA shooters for years. As stated before, base of bullet even with base of neck. Make sure you size your brass so it fits your chamber well. Firm grip on closing. Most large groups I have seen coming from TC in 7TCU were due to unequal neck tension, poor sizing for the chamber, or bad crown. Two of the three are loading technique.

Hope this helps!

Steve

My honey load for all my 7 TCU's is 27.2 grains of Varget with a 139-140 grain bullet. Sierras have always shot well, but what I use now due to cost savings is a 140 Prvi Partizan. Shoots as well as any load I have had aside from 130 Sierra match bullets with a lot less expense. H322 works very well, too.

Hi
I used to have a 7TCU barrel that would not shoot well with anything but 120 gr bullets. It shot them well but did not like the middle or heavy weights. I know it is strange but that is what I found. I used AA2015 with the 120 gr. bullets.
John

The one thing all my 7TCU's agree on is 27.2 grains of Varget with a 140 grain bullet. I use a Prvi Partizan 140 just because at one time they were cheap, though the price has kept creeping up the past few years. I had unbelievable results from the 130 Sierra Match bullet.